Hagstrom Electronics USB-ASC232 User manual
USB-ASC232
ASCII RS-232 Controlled USB
Keyboard and Mouse Cable
User Manual
Toll Free 888-690-9080
Phone: (540) 465-4677 Fax: (540) 465-4678
Monday through Friday, 8:00 am to 5:00 pm (EST)
www.hagstromelectronics.com
1986 Junction Road, Strasburg, VA 22657
Copyright © 2020 HAGSTROM ELECTRONICS, INC.
V. 04.20
HAGSTROM
ELECTRONICS, INC.
Warranty
HAGSTROM ELECTRONICS, INC. warrants this
product against defects in material or workmanship for a
period of ONE YEAR from the original purchase date. We will
repair or replace (at our option) the returned defective unit
at no charge during this warranty period.
No responsibility is assumed for any special, incidental,
or consequential damage resulting from the use of or
inability to use this product. In no case is HAGSTROM
ELECTRONICS, INC. to be liable for any amount which
exceeds the purchase price of the unit, regardless of the
claim.
No other warranty, written or verbal, is authorized. This
warranty is applicable only to units sold in the United States.
Units sold outside the United States are covered by a similar
warranty.
Depending on the state in which you live, you may have additional rights.
Great care has been taken during the assembly, testing, and burn-in of
your USB-ASC232 to ensure its performance. If you have any questions,
please send us an email or give us a call. Support is available Monday
through Friday, 8:00 am to 5:00 pm (EST).
Call Toll Free 888-690-9080, or (540) 465-4677
NOTICE: The USB-ASC232 product is designed to be used by
technically oriented computer users.
Thank you for purchasing the model USB-ASC232 Cable
HAGSTROM ELECTRONICS, INC.
is pleased that you have selected this product for your application.
This unit is may be used a variety of ways in order to meet your
specific requirements. Please take a few minutes to read this
manual before using your USB-ASC232.
If you have any questions about the use of the USB-ASC232
not covered in this manual, please contact us directly. We offer
toll free technical product support from 8:00am to 5:00pm M-F
Eastern Time 888-690-9080. You may also send an email to
We respond to all email requests within one business day.
Introduction to the USB-ASC232 3
Translation Modes of the USB-ASC232 3
ASCII Mode 3
Extended ASCII Mode 4
Key Number Number Mode 6
Additional Key Number Mode Commands 8
Key Number Mode Examples 9
Producing Mouse Action on the Target Computer 10
Mouse Packet Examples 12
Sending Serial Control Commands 13
USB-ASC232 Configuration Program
Serial Connector Pinout
14
17
Questions or Comments?
Please give us a call!
Toll Free
888-690-9080
or
www.hagstromelectronics.com
email: sales@hagstromelectronics.com
17 2
CONTENTS
Operating Voltage 5 Volts DC +/- 5%
(Powered from USB port)
Operating Current Less than 100 ma
Operating Temp. 0 to 70 Degrees C
PC Interface USB - Target Computer
RS-232 - Serial Source
Cable Length 6 feet
USB-ASC232 Specifications
PIN 2
TXD
PIN 3
RXD
PIN 5
GND
Serial Connector Pinout
The USB-ASC232 serial connection is a 9 pin female D type
connector. The pinout is designed such that it will attach directly
to a standard PC com port.
Pin 1 = Unused
Pin 2 = Serial Data out of USB-ASC232
Pin 3 = Serial Data into USB-ASC232
Pin 4 = Unused
Pin 5 = Logic Ground
Pin 6 = Unused
Pin 7 = CTS into USB-ASC232
Pin 8 = RTS out of USB-ASC232
Pin 9 = Unused Looking into connector face
PIN 7
CTS
PIN 8
RTS
Introduction to the USB-ASC232
The USB-ASC232 Keyboard and Mouse Emulator is a product designed
to allow RS-232 serial communication to produce USB keystroke and
mouse actions on a target computer.
The USB end of this device can be connected to any USB port that
supports a standard USB Keyboard and Mouse. No special drivers
are required.
The USB-ASC232 is configurable to allow for different standard BAUD
rates, stop bits, parity, handshaking, and mode of translation. Use the
supplied “USBASC232.EXE” program to configure the unit.
Translation Modes of the USB-ASC232
There are three specific translation modes in which the USB-ASC232
can be programmed to operate. Incoming RS-232 data can be
translated from ASCII Mode, Extended ASCII Mode, or Key Number
Mode. Each of these modes vary in the way incoming characters are
treated and their translation into USB keystrokes.
ASCII MODE (Default Mode)
The ASCII mode is the default factory setting for the mode of operation.
In this mode, printable ASCII characters received, which are each a
one byte value in the range of 0x00 to 0x7F (0 to 127 decimal), will
generate their corresponding USB keystroke on the computer where
the USB-ASC232 USB plug is connected. See the ASCII table on
the next page for a list of the characters which are recognized and
translated for the cable’s ASCII mode of operation.
Example: If a one byte value of 0x41 (decimal 65) is received in this
mode, a capital “A” character will be produced as a keystroke on the
computer at the USB end of the cable.
RS-232 characters received which are out of the 0x00 to 0x7f range
will be ignored in this mode.
3
Saving the Configuration to the USB-ASC232
Once the desired parameters have been set on the USBASC232
Configuration Utility Screen, it must be saved to the USB-ASC232 unit
to begin operation according to those settings.
Select the button “Save To USBASC232” to write the configuration to
the unit. Once the configuration has been written, the USB-ASC232
will begin immediately operating according to the loaded parameters.
The configuration may also be read from the USB-ASC232 unit by
selecting the button “Read From USB-ASC232”. The configuration
in the USB-ASC232 attached to the computer’s USB port will be read
into the configuration parameters on the screen.
Once a configuration has been created, it is recommended that it be
stored on the computer so that it may be recalled at a later time. Use
the “File” menu to perform saving and opening of configurations.
Saving the configuration to a file on the computer provides an easy
way to recall the same configuration to save into additional USB-
ASC232 units.
Custom USB-ASC232 Options
We offer special modifications to our standard USB-ASC232 unit to conform to your
exact specifications. Potential modifications include, but are not limited to: special
cable lengths, different gender DB9, RS-422, etc. Let us know if you have special
requirements. Please call or email with your specific custom needs.
16
4
Value Character Value Character Value Character Value Character
Dec Hex Dec Hex Dec Hex Dec Hex
00
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
00
01
02
03
04
05
06
07
08
09
0A
0B
0C
0D
0E
0F
10
11
12
13
14
15
16
17
18
19
1A
1B
1C
1D
1E
1F
none
none
none
none
none
none
none
none
Backspace
Tab
none
none
none
Return
none
none
none
none
none
none
none
none
none
none
none
none
none
Esc
none
none
none
none
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
20
21
22
23
24
25
26
27
28
29
2A
2B
2C
2D
2E
2F
30
31
32
33
34
35
36
37
38
39
3A
3B
3C
3D
3E
3F
Space
!
“
#
$
%
&
‘
(
)
*
+
,
_
.
/
0
1
2
3
4
5
6
7
8
9
:
;
<
=
>
?
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
40
41
42
43
44
45
46
47
48
49
4A
4B
4C
4D
4E
4F
50
51
52
53
54
55
56
57
58
59
5A
5B
5C
5D
5E
5F
@
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
Q
R
S
T
U
V
W
X
Y
Z
[
\
]
^
-
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
60
61
62
63
64
65
66
67
68
69
6A
6B
6C
6D
6E
6F
70
71
72
73
74
75
76
77
78
79
7A
7B
7C
7D
7E
7F
`
a
b
c
d
e
f
g
h
i
j
k
l
m
n
o
p
q
r
s
t
u
v
w
x
y
z
{
|
}
~
none
ASCII Mode Translation Table
The ASCII mode table below lists the standard ASCII characters that
will produce a corresponding USB keystroke when received by the
USB-ASC232.
Extended ASCII Mode
The USB-ASC232 Extended ASCII Mode of operation allows for the
standard ASCII character set (character values 0x00 to 0x7F), in
addition to an extended ASCII character set (character values 0x80 to
0xFF). When an RS-232 byte is received in this mode, it produces a
USB keystroke on the PC which corresponds to the following table.
Parity may be set to “None”, “Odd”, or “Even”.
The number of stop bits may be set to 1 or 2 bits.
Handshaking may be set to “None”, “RTS/CTS”, or “Echo”.
When the handshaking is set to “None”, the computer sending the
information must be careful not to overflow the receiving buffer of
the USB-ASC232. The best way to do avoid the buffer overflow
in this mode is to delay 50msec after each byte is sent to the USB-
ASC232.
With handshaking set to “RTS/CTS”, the hardware controls the
flow of data between the computer sending the RS-232 data and
the USB-ASC232. This hardware handshaking prevents overflow
of the receiving buffer on the USB-ASC232 unit. When “RTS/CTS”
is used for handshaking, the DTR options for the serial port being
used on the computer sending the RTS-232 should be disabled.
The “Echo” setting means that the USB-ASC232 will send a one’s
complement response byte to each command. For instance, if a
value of 0x32 is sent to the USB-ASC232 serial port, it will reply
with a value of 0xCD in response. Use this handshaking mode as
a way to not only keep the buffer from overflowing, but is also a
confirmation of the value of the code that was received.
Note that in the “Echo” handshake mode, the response to the
0x7F request for LED status in Key Number Mode will be replied
with the status byte as outlined on page 8.
In “Echo” mode, the individual bytes of the mouse control packet
do not generate a reply. Only after the 4th and last byte of the
mouse packet has been received is an echo value of 0xFF returned
to indicate reception of the mouse packet.
15
5
Value Character Value Character Value Character Value Character
Dec Hex Dec Hex Dec Hex Dec Hex
00
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
00
01
02
03
04
05
06
07
08
09
0A
0B
0C
0D
0E
0F
10
11
12
13
14
15
16
17
18
19
1A
1B
1C
1D
1E
1F
none
none
none
none
none
none
none
none
Backspace
Tab
none
none
none
Return
F11
F12
none
F1
F2
F3
F4
F5
F6
F7
F8
F9
F10
Esc
none
none
none
none
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
20
21
22
23
24
25
26
27
28
29
2A
2B
2C
2D
2E
2F
30
31
32
33
34
35
36
37
38
39
3A
3B
3C
3D
3E
3F
Space
!
“
#
$
%
&
‘
(
)
*
+
,
_
.
/
0
1
2
3
4
5
6
7
8
9
:
;
<
=
>
?
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
40
41
42
43
44
45
46
47
48
49
4A
4B
4C
4D
4E
4F
50
51
52
53
54
55
56
57
58
59
5A
5B
5C
5D
5E
5F
@
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
Q
R
S
T
U
V
W
X
Y
Z
[
\
]
^
-
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
60
61
62
63
64
65
66
67
68
69
6A
6B
6C
6D
6E
6F
70
71
72
73
74
75
76
77
78
79
7A
7B
7C
7D
7E
7F
`
a
b
c
d
e
f
g
h
i
j
k
l
m
n
o
p
q
r
s
t
u
v
w
x
y
z
{
|
}
~
none
Value Character Value Character Value Character Value Character
Dec Hex Dec Hex Dec Hex Dec Hex
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
80
81
82
83
84
85
86
87
88
89
8A
8B
8C
8D
8E
8F
90
91
92
93
94
95
96
97
98
99
9A
9B
9C
9D
9E
9F
€
none
‚
ƒ
„
…
†
‡
ˆ
‰
Š
‹
Œ
none
Ž
none
none
‘
’
“
”
•
–
—
˜
™
š
›
œ
none
ž
Ÿ
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
A0
A1
A2
A3
A4
A5
A6
A7
A8
A9
AA
AB
AC
AD
AE
AF
B0
B1
B2
B3
B4
B5
B6
B7
B8
B9
BA
BB
BC
BD
BE
BF
nb Space
¡
¢
£
¤
¥
¦
§
¨
©
ª
«
¬
none
®
¯
°
±
²
³
´
µ
¶
·
¸
¹
º
»
¼
½
¾
¿
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
C0
C1
C2
C3
C4
C5
C6
C7
C8
C9
CA
CB
CC
CD
CE
CF
D0
D1
D2
D3
D4
D5
D6
D7
D8
D9
DA
DB
DC
DD
DE
DF
À
Á
Â
Ã
Ä
Å
Æ
Ç
È
É
Ê
Ë
Ì
Í
Î
Ï
Ð
Ñ
Ò
Ó
Ô
Õ
Ö
×
Ø
Ù
Ú
Û
Ü
Ý
ß
à
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
E0
E1
E2
E3
E4
E5
E6
E7
E8
E9
EA
EB
EC
ED
EE
EF
F0
F1
F2
F3
F4
F5
F6
F7
F8
F9
FA
FB
FC
FD
FE
FF
à
á
â
ã
ä
å
æ
ç
è
é
ê
ë
ì
í
î
ï
ð
ñ
ò
ó
ô
õ
ö
÷
ø
ù
ú
û
ü
ý
þ
ÿ
Extended ASCII Mode Translation Table
14
USB-ASC232 Configuration Program
The USB-ASC232 has programmable settings for adapting the
interface to the user’s application.
A program, “USBASC232.EXE” is included on the supplied CD.
Copy the entire contents of the CD into a folder on the (USB end)
target computer’s hard disk and run the .exe file from that folder.
There are a variety of protocol settings which can be selected from
the USBASC232.EXE configuration utility.
To create a configuration using the utility, first select the “Mode”
menu and choose ASCII, Extended ASCII, or Key Number Mode
based on the desired conversion mode.
Next, set the RS-232 communication parameters for the Baud
Rate, Number of Bits in the character, Parity, Number of Stop Bits,
and Handshaking mode.
The standard BAUD rates available are 2400, 4800, 9600,
14400, 19200, and 38400.
The number of bits in the character sent to the USB-ASC232 may
be 7 bits or 8 bits. NOTE: 8 bit characters are required for Ex-
tended ASCII and Key Number modes.
When using the Extended ASCII mode, characters are received which
are in the range of value from 0x00 to 0xFF (0 to 255 decimal). The
corresponding USB keystroke from the table will be generated.
Extended ASCII Mode allows for the ANSI/ISO Latin-1 character group
in the range of 0x80 to 0xFF (128 to 255 decimal) to be produced as
well as the standard 0x00 through 0x7F ASCII codes. Additionally in
this mode, the F1-F10 keys are supported for the character range of
codes 0x11 to 0x1A values respectively. F11 and F12 keys are sent for
received characters of 0x0E and 0x0F in the Extended ASCII mode.
Example 1: If the value 0x41 (decimal 65) is received in this mode, a
capital “A” character will be produced on the target computer at the
USB end of the cable.
Example 2: If the value 0xA9 (decimal 169) is received in this mode,
a “©” character will be produced on the target computer at the USB
end of the cable.
Key Number Mode
The Key Number Mode provides users with complete control of the
generation of the make (activation) and break (deactivation) of any
standard keyboard key. In this mode, a single byte will command
the make or break of a specific keyboard key at the target computer.
Using this mode allows for generation of any keystroke or combination
of keystrokes on the target computer.
In general, to make a key (generate a press of a specific key), a one
byte value between 0x00 and 0x7F is sent to the USB-ASC232. Once
received, the key specified will be seen as held down on the computer
just as if someone was physically holding that key on a keyboard.
Each time a make is sent for a key, a corresponding break (release) of
that key must be done at a later time to deactivate it. The break code
for a key is the same value as the make code plus 0x80 (128 decimal).
The break code releases the key that was activated earlier by a make
code. See the following table for make and break codes.
613
How far the scroll moves on the computer screen depends on the
scroll system settings of the target computer.
0x00, 0x00, 0x00, 0x18
The next example four RS-232 mouse packets are sent to emulate
a double left mouse click on the target computer.
Packet 1 - 0x00, 0x00, 0x00, 0x09 (left mouse button on)
Now delay around 150 msec for the system to see the button
Packet 2 - 0x00, 0x00, 0x00, 0x08 (left mouse button off)
Delay 150 msec again for the system to see the button release
Packet 3 - 0x00, 0x00, 0x00, 0x09 (left mouse button on)
Delay around 150 msec for the system to see the button
Packet 4 - 0x00, 0x00, 0x00, 0x08 (left mouse button off)
Note that cursor movement, scroll wheel movement and button
actions may all be implemented within the same packet. The
examples above focus only on a particular action at a time for
clarity. For instance, a command that sends both X and Y cusor
movement can also send button information and/or scroll wheel
movement.
Sending Serial Control Commands
The CD included with the unit contains source code examples in
various programming languages to help the user get started on
their own Com Port control software. Use these examples as a
starting point for programs which run the communication to the
USB-ASC232 from the computer attached to the USB-ASC232
Com Port DB9 connector.
US Key Number Table (Decimal Values)
An international key number table is available on the CD provided with the USB-ASC232.
7
Key Make Break
`~ 01 129
1! 02 130
2@ 03 131
3# 04 132
4$ 05 133
5% 06 134
6^ 07 135
7& 08 136
8* 09 137
9( 10 138
0) 11 139
-_ 12 140
=+ 13 141
BS 15 143
Tab 16 144
Q 17 145
W 18 146
E 19 147
R 20 148
T 21 149
Y 22 150
U 23 151
I 24 152
O 25 153
P 26 154
[{ 27 155
]} 28 156
\| 29 157
Caps 30 158
A 31 159
S 32 160
D 33 161
F 34 162
G 35 163
H 36 164
Key Make Break
J 37 165
K 38 166
L 39 167
;: 40 168
‘“ 41 169
Enter 43 171
L Shift 44 172
Z 46 174
X 47 175
C 48 176
V 49 177
B 50 178
N 51 179
M 52 180
,< 53 181
.> 54 182
/? 55 183
R Shift 57 185
L Ctrl 58 186
L Alt 60 188
Space 61 189
R Alt 62 190
R Ctrl 64 192
L Win 70 198
R Win 71 199
Win APL 72 200
Insert 75 203
Delete 76 204
L Arrow 79 207
Home 80 208
End 81 209
Up Arrow 83 211
Dn Arrow 84 212
Page Up 85 213
Page Dn 86 214
Key Make Break
R Arrow 89 217
NumLock 90 218
7 (Num) 91 219
4 (Num) 92 220
1 (Num) 93 221
/ (Num) 95 223
8 (Num) 96 224
5 (Num) 97 225
2 (Num) 98 226
0 (Num) 99 227
* (Num) 100 228
9 (Num) 101 229
6 (Num) 102 230
3 (Num) 103 231
. (Num) 104 232
- (Num) 105 233
+ (Num) 106 234
Enter (Num) 108 236
Esc 110 238
F1 112 240
F2 113 241
F3 114 242
F4 115 243
F5 116 244
F6 117 245
F7 118 246
F8 119 247
F9 120 248
F10 121 249
F11 122 250
F12 123 251
Prt Scr 124 252
Scrl Lk 125 253
Pause/Break 126 254
When sending data to the USB-ASC232 to generate keystrokes in
Key Number Mode, use the values shown above to produce the
“make” and “break” actions for the corresponding key.
12
When sending a mouse control packet for cursor movement only,
be sure to send all “0” values for the scroll wheel and mouse
button bits, if those options are not being used for mouse actions
at that time.
Mouse Packet Examples
The packet below is an example of a packet for the USB-ASC232
to command X movement of 15 to the right, and a Y movement
of 5 in the up direction.
0x00, 0x0F, 0xFB, 0x08
The movement values shown above do not necesarily coordinate to
a specific number of pixels moved as the computer mouse settings
for speed and acceleration determine the actual cursor movement
for the target computer. The movement of the mouse cursor for
the values sent will be repeatable for a specifc computer.
All mouse cusor control movements function just as a standard
mouse in that all movement is relative from the current cursor
position. The USB-ASC232 does not send or receive any specific
screen coordinates from the computer.
To position the mouse cursor to a specific point on the computer
screen, first send enough movement to put the cursor into a
known position, such as the upper left of the screen, and then
use additional mouse movement commands to get the cursor to
the desired location. The values used to get the cursor to the
desired screen position from the known (upper left in this case)
position will be repeatable each time for a specific computer and
other computers with the exact same screen settings and mouse
settings.
The following packet can be used to send the scroll wheel
command of up one position to the computer.
8
By using the make and break commands in Key Number Mode, any
sequence that can by manually typed on a keyboard can be produced
with the USB-ASC232. Use this Key Number Mode to emulate single
keystrokes or even combinations such as Ctrl+F1, or Shift-Alt+F5.
Additional Key Number Mode Control Commands
The USB-ASC232 features two additional commands for keyboard
action. The first command provides a way to clear the keyboard buffer
and is useful for ensuring that no keys are stuck in the “ON” state. The
second command allows for the polling of the keyboard status LED
states. This polling command is useful for checking shift case changes,
or for making sure of the Num Lock state before using Num Lock
affected keys.
0x38 - USB Buffer Clear Command. Sending 0x38 to the
USB-ASC232 serial port results in the device’s internal USB keyboard
buffer being cleared. Use of this command ensures that all made keys
currently in the keyboard buffer are released.
0x7F - Status LED Read Command. Sending a code 0x7F to the USB-
ASC232 serial port results in the return of a character in the range of ASCII
“0” - “7”. The USB-ASC232 response character reflects the current
state of the Scroll Lock, Caps Lock, and Num Lock LEDs on the computer
system as listed in the chart below.
ASCII Response Scroll Lock Status Caps Lock Status Num Lock Status
“0” Off Off Off
“1” Off Off On
“2” Off On Off
“3’ Off On On
“4” On Off Off
“5” On Off On
“6” On On Off
“7” On On On
11
[W2] - The most significant bit of the scroll wheel movement
magnitude.
[W1] - Bit 1 of the three bit value for scroll wheel movement.
[W0] - Least significant bit of the scroll wheel movement value.
[1] - Bit 3 of this #4 byte is always “1”. Sending “0” for this bit will
cause the entire mouse control packet to be ignored.
[MM] - State of the middle mouse button. Set to 1 for middle
mouse button on, 0 for the button to be off.
[MR] - State of the right mouse button. Set to 1 for right mouse
button on, 0 for the button to be off.
[ML] - State of the left mouse button. Set to 1 for left mouse
button on, 0 for the button to be off.
NOTES - When sending this 4 byte mouse command packet, the
three bytes following the first 0x00 byte should be sent with no
more than 50msec between the bytes. The 0x00 must always
be followed by 3 additional bytes to complete the mouse control
packet and avoid any confusion between mouse control and
keystroke commands.
The scroll wheel magnitude command is a 4 bit signed value
located in bits Ws through W0, and in the range of 0x00 to 0x07
for up movement, 0x0F to 0x08 for down movement.
The three mouse button bits command the states of the mouse
buttons as seen by the target computer. A “1” in the respective
bit indicates the mouse button is on, while a “0” indicates the
button is not on. Be sure to release any mouse buttons that were
in the on state at a later time once the mouse button task has
completed.
9
Key Number Mode Examples
Generation of keystrokes on the target computer is done through
the sending of special one byte codes in the Key Number Mode.
Each standard key of the PC keyboard is assigned a “make” code
to emulate the press of a key, and a “break” code, which results in
the release of the key. The Key Number Table on the page 7
lists each of the supported keys and their corresponding make
and break codes.
From the keycode table, the value of 02 (0x02) can be sent to
the unit to generate the “make” or press and hold of the “1” key.
Sending a byte with a value of 130 (0x82) will result in the release
of the “1” key.
Important: For any key that has been previously sent a “make”
code, a “break” code of that key must be sent at a later time.
Failure to send the corresponding break code will leave the key in
the down state on the target computer, which may result in unin-
tended keystrokes when new commands are sent. The last key left
in the make state without a break will repeat until the break code
is sent. Never command more than 60 keys in the “make” state
at the same time as this will exceed the standard USB protocol
keyboard buffer length for the USB-ASC232 device.
The use of make and break codes allows the user to create virtu-
ally any keystroke combination. For example, if a sequence of
CTRL+ALT+F1 was needed, the following codes would be sent,
58 (L Ctrl make), 60 (L Alt make), 112 (Make F1), 240 (Break
F1), 188 (Break L Alt), 186 (Break L Ctrl).
The example above assumes that the handshaking USB-ASC232
is seen as not busy before sending the next command byte to the
unit.
Producing Mouse Action on the Target PC
The USB-ASC232 is capable of controlling the mouse cursor and
mouse button states through a special four byte command sequence.
This command sequence can be used in any of the operating modes
of the USB-ASC232.
The four byte mouse control sequence is construced as follows:
Byte #1 Byte #2 Byte #3 Byte #4
[Command] [X Movement] [Y Movement] [Scroll/Buttons]
Byte #1 - Always a 0x00 value, indicates start of packet.
Byte #2 - Signed byte for the magnitude of X direction movement.
Values 0x01 to 0x7F move the cursor right, values 0xFF to 0x81
move it left. A 0x00 Value produces no X direction movement.
Byte #3 - Signed byte for the magnitude of Y direction movement.
Values 0x01 to 0x7F move the cursor down, values 0xFF to 0x81
move the cursor up. A 0x00 produces no Y movement.
Byte #4 - Byte for Scroll Wheel movement and mouse button
control. The upper 4 bits of this byte contain a signed value for
scroll wheel movement, while the lower 3 bits command the mouse
Left, Right, and Middle button activation and deactivation.
This Byte #4 is constructed as shown,
Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
[Ws] [W2] [W1] [W0] [1] [MM] [MR] [ML]
[Ws] - The sign of the scroll wheel movement. A zero in this bit
commands up movement on the scroll wheel, a one in this bit
produces down scroll wheel movement. Movement magnitude
based on the signed value in Ws through W0 values.
10
9
Key Number Mode Examples
Generation of keystrokes on the target computer is done through
the sending of special one byte codes in the Key Number Mode.
Each standard key of the PC keyboard is assigned a “make” code
to emulate the press of a key, and a “break” code, which results in
the release of the key. The Key Number Table on the page 7
lists each of the supported keys and their corresponding make
and break codes.
From the keycode table, the value of 02 (0x02) can be sent to
the unit to generate the “make” or press and hold of the “1” key.
Sending a byte with a value of 130 (0x82) will result in the release
of the “1” key.
Important: For any key that has been previously sent a “make”
code, a “break” code of that key must be sent at a later time.
Failure to send the corresponding break code will leave the key in
the down state on the target computer, which may result in unin-
tended keystrokes when new commands are sent. The last key left
in the make state without a break will repeat until the break code
is sent. Never command more than 60 keys in the “make” state
at the same time as this will exceed the standard USB protocol
keyboard buffer length for the USB-ASC232 device.
The use of make and break codes allows the user to create virtu-
ally any keystroke combination. For example, if a sequence of
CTRL+ALT+F1 was needed, the following codes would be sent,
58 (L Ctrl make), 60 (L Alt make), 112 (Make F1), 240 (Break
F1), 188 (Break L Alt), 186 (Break L Ctrl).
The example above assumes that the handshaking USB-ASC232
is seen as not busy before sending the next command byte to the
unit.
Producing Mouse Action on the Target PC
The USB-ASC232 is capable of controlling the mouse cursor and
mouse button states through a special four byte command sequence.
This command sequence can be used in any of the operating modes
of the USB-ASC232.
The four byte mouse control sequence is construced as follows:
Byte #1 Byte #2 Byte #3 Byte #4
[Command] [X Movement] [Y Movement] [Scroll/Buttons]
Byte #1 - Always a 0x00 value, indicates start of packet.
Byte #2 - Signed byte for the magnitude of X direction movement.
Values 0x01 to 0x7F move the cursor right, values 0xFF to 0x81
move it left. A 0x00 Value produces no X direction movement.
Byte #3 - Signed byte for the magnitude of Y direction movement.
Values 0x01 to 0x7F move the cursor down, values 0xFF to 0x81
move the cursor up. A 0x00 produces no Y movement.
Byte #4 - Byte for Scroll Wheel movement and mouse button
control. The upper 4 bits of this byte contain a signed value for
scroll wheel movement, while the lower 3 bits command the mouse
Left, Right, and Middle button activation and deactivation.
This Byte #4 is constructed as shown,
Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
[Ws] [W2] [W1] [W0] [1] [MM] [MR] [ML]
[Ws] - The sign of the scroll wheel movement. A zero in this bit
commands up movement on the scroll wheel, a one in this bit
produces down scroll wheel movement. Movement magnitude
based on the signed value in Ws through W0 values.
10
8
By using the make and break commands in Key Number Mode, any
sequence that can by manually typed on a keyboard can be produced
with the USB-ASC232. Use this Key Number Mode to emulate single
keystrokes or even combinations such as Ctrl+F1, or Shift-Alt+F5.
Additional Key Number Mode Control Commands
The USB-ASC232 features two additional commands for keyboard
action. The first command provides a way to clear the keyboard buffer
and is useful for ensuring that no keys are stuck in the “ON” state. The
second command allows for the polling of the keyboard status LED
states. This polling command is useful for checking shift case changes,
or for making sure of the Num Lock state before using Num Lock
affected keys.
0x38 - USB Buffer Clear Command. Sending 0x38 to the
USB-ASC232 serial port results in the device’s internal USB keyboard
buffer being cleared. Use of this command ensures that all made keys
currently in the keyboard buffer are released. The USB-ASC232 will
respond to this command with 0xC7, which is the one’s complement of
the command.
0x7F - Status LED Read Command. Sending a code 0x7F to the USB-
ASC232 serial port results in the return of a character in the range of ASCII
“0” - “7”. The USB-ASC232 response character reflects the current
state of the Scroll Lock, Caps Lock, and Num Lock LEDs on the computer
system as listed in the chart below.
ASCII Response Scroll Lock Status Caps Lock Status Num Lock Status
“0” Off Off Off
“1” Off Off On
“2” Off On Off
“3’ Off On On
“4” On Off Off
“5” On Off On
“6” On On Off
“7” On On On
11
[W2] - The most significant bit of the scroll wheel movement
magnitude.
[W1] - Bit 1 of the three bit value for scroll wheel movement.
[W0] - Least significant bit of the scroll wheel movement value.
[1] - Bit 3 of this #4 byte is always “1”. Sending “0” for this bit will
cause the entire mouse control packet to be ignored.
[MM] - State of the middle mouse button. Set to 1 for middle
mouse button on, 0 for the button to be off.
[MR] - State of the right mouse button. Set to 1 for right mouse
button on, 0 for the button to be off.
[ML] - State of the left mouse button. Set to 1 for left mouse
button on, 0 for the button to be off.
NOTES - When sending this 4 byte mouse command packet, the
three bytes following the first 0x00 byte should be sent with no
more than 50msec between the bytes. The 0x00 must always
be followed by 3 additional bytes to complete the mouse control
packet and avoid any confusion between mouse control and
keystroke commands.
The scroll wheel magnitude command is a 4 bit signed value
located in bits Ws through W0, and in the range of 0x00 to 0x07
for up movement, 0x0F to 0x08 for down movement.
The three mouse button bits command the states of the mouse
buttons as seen by the target computer. A “1” in the respective
bit indicates the mouse button is on, while a “0” indicates the
button is not on. Be sure to release any mouse buttons that were
in the on state at a later time once the mouse button task has
completed.
US Key Number Table (Decimal Values)
An international key number table is available on the CD provided with the USB-ASC232.
7
Key Make Break
`~ 01 129
1! 02 130
2@ 03 131
3# 04 132
4$ 05 133
5% 06 134
6^ 07 135
7& 08 136
8* 09 137
9( 10 138
0) 11 139
-_ 12 140
=+ 13 141
BS 15 143
Tab 16 144
Q 17 145
W 18 146
E 19 147
R 20 148
T 21 149
Y 22 150
U 23 151
I 24 152
O 25 153
P 26 154
[{ 27 155
]} 28 156
\| 29 157
Caps 30 158
A 31 159
S 32 160
D 33 161
F 34 162
G 35 163
H 36 164
Key Make Break
J 37 165
K 38 166
L 39 167
;: 40 168
‘“ 41 169
Enter 43 171
L Shift 44 172
Z 46 174
X 47 175
C 48 176
V 49 177
B 50 178
N 51 179
M 52 180
,< 53 181
.> 54 182
/? 55 183
R Shift 57 185
L Ctrl 58 186
L Alt 60 188
Space 61 189
R Alt 62 190
R Ctrl 64 192
L Win 70 198
R Win 71 199
Win APL 72 200
Insert 75 203
Delete 76 204
L Arrow 79 207
Home 80 208
End 81 209
Up Arrow 83 211
Dn Arrow 84 212
Page Up 85 213
Page Dn 86 214
Key Make Break
R Arrow 89 217
NumLock 90 218
7 (Num) 91 219
4 (Num) 92 220
1 (Num) 93 221
/ (Num) 95 223
8 (Num) 96 224
5 (Num) 97 225
2 (Num) 98 226
0 (Num) 99 227
* (Num) 100 228
9 (Num) 101 229
6 (Num) 102 230
3 (Num) 103 231
. (Num) 104 232
- (Num) 105 233
+ (Num) 106 234
Enter (Num) 108 236
Esc 110 238
F1 112 240
F2 113 241
F3 114 242
F4 115 243
F5 116 244
F6 117 245
F7 118 246
F8 119 247
F9 120 248
F10 121 249
F11 122 250
F12 123 251
Prt Scr 124 252
Scrl Lk 125 253
Pause/Break 126 254
When sending data to the USB-ASC232 to generate keystrokes in
Key Number Mode, use the values shown above to produce the
“make” and “break” actions for the corresponding key.
12
When sending a mouse control packet for cursor movement only,
be sure to send all “0” values for the scroll wheel and mouse
button bits, if those options are not being used for mouse actions
at that time.
Mouse Packet Examples
The packet below is an example of a packet for the USB-ASC232
to command X movement of 15 to the right, and a Y movement
of 5 in the up direction.
0x00, 0x0F, 0xFB, 0x08
The movement values shown above do not necesarily coordinate to
a specific number of pixels moved as the computer mouse settings
for speed and acceleration determine the actual cursor movement
for the target computer. The movement of the mouse cursor for
the values sent will be repeatable for a specifc computer.
All mouse cusor control movements function just as a standard
mouse in that all movement is relative from the current cursor
position. The USB-ASC232 does not send or receive any specific
screen coordinates from the computer.
To position the mouse cursor to a specific point on the computer
screen, first send enough movement to put the cursor into a
known position, such as the upper left of the screen, and then
use additional mouse movement commands to get the cursor to
the desired location. The values used to get the cursor to the
desired screen position from the known (upper left in this case)
position will be repeatable each time for a specific computer and
other computers with the exact same screen settings and mouse
settings.
The following packet can be used to send the scroll wheel
command of up one position to the computer.
When using the Extended ASCII mode, characters are received which
are in the range of value from 0x00 to 0xFF (0 to 255 decimal). The
corresponding USB keystroke from the table will be generated.
Extended ASCII Mode allows for the ANSI/ISO Latin-1 character group
in the range of 0x80 to 0xFF (128 to 255 decimal) to be produced as
well as the standard 0x00 through 0x7F ASCII codes. Additionally in
this mode, the F1-F10 keys are supported for the character range of
codes 0x11 to 0x1A values respectively. F11 and F12 keys are sent for
received characters of 0x0E and 0x0F in the Extended ASCII mode.
Example 1: If the value 0x41 (decimal 65) is received in this mode, a
capital “A” character will be produced on the target computer at the
USB end of the cable.
Example 2: If the value 0xA9 (decimal 169) is received in this mode,
a “©” character will be produced on the target computer at the USB
end of the cable.
Key Number Mode
The Key Number Mode provides users with complete control of the
generation of the make (activation) and break (deactivation) of any
standard keyboard key. In this mode, a single byte will command
the make or break of a specific keyboard key at the target computer.
Using this mode allows for generation of any keystroke or combination
of keystrokes on the target computer.
In general, to make a key (generate a press of a specific key), a one
byte value between 0x00 and 0x7F is sent to the USB-ASC232. Once
received, the key specified will be seen as held down on the computer
just as if someone was physically holding that key on a keyboard.
Each time a make is sent for a key, a corresponding break (release) of
that key must be done at a later time to deactivate it. The break code
for a key is the same value as the make code plus 0x80 (128 decimal).
The break code releases the key that was activated earlier by a make
code. See the following table for make and break codes.
613
How far the scroll moves on the computer screen depends on the
scroll system settings of the target computer.
0x00, 0x00, 0x00, 0x18
The next example four RS-232 mouse packets are sent to emulate
a double left mouse click on the target computer.
Packet 1 - 0x00, 0x00, 0x00, 0x09 (left mouse button on)
Now delay around 150 msec for the system to see the button
Packet 2 - 0x00, 0x00, 0x00, 0x08 (left mouse button off)
Delay 150 msec again for the system to see the button release
Packet 3 - 0x00, 0x00, 0x00, 0x09 (left mouse button on)
Delay around 150 msec for the system to see the button
Packet 4 - 0x00, 0x00, 0x00, 0x08 (left mouse button off)
Note that cursor movement, scroll wheel movement and button
actions may all be implemented within the same packet. The
examples above focus only on a particular action at a time for
clarity. For instance, a command that sends both X and Y cusor
movement can also send button information and/or scroll wheel
movement.
Sending Serial Control Commands
The CD included with the unit contains source code examples in
various programming languages to help the user get started on
their own Com Port control software. Use these examples as a
starting point for programs which run the communication to the
USB-ASC232 from the computer attached to the USB-ASC232
Com Port DB9 connector.
5
Value Character Value Character Value Character Value Character
Dec Hex Dec Hex Dec Hex Dec Hex
00
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
00
01
02
03
04
05
06
07
08
09
0A
0B
0C
0D
0E
0F
10
11
12
13
14
15
16
17
18
19
1A
1B
1C
1D
1E
1F
none
none
none
none
none
none
none
none
Backspace
Tab
none
none
none
Return
none
none
none
none
none
none
none
none
none
none
none
none
none
Esc
none
none
none
none
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
20
21
22
23
24
25
26
27
28
29
2A
2B
2C
2D
2E
2F
30
31
32
33
34
35
36
37
38
39
3A
3B
3C
3D
3E
3F
Space
!
“
#
$
%
&
‘
(
)
*
+
,
_
.
/
0
1
2
3
4
5
6
7
8
9
:
;
<
=
>
?
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
40
41
42
43
44
45
46
47
48
49
4A
4B
4C
4D
4E
4F
50
51
52
53
54
55
56
57
58
59
5A
5B
5C
5D
5E
5F
@
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
Q
R
S
T
U
V
W
X
Y
Z
[
\
]
^
-
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
60
61
62
63
64
65
66
67
68
69
6A
6B
6C
6D
6E
6F
70
71
72
73
74
75
76
77
78
79
7A
7B
7C
7D
7E
7F
`
a
b
c
d
e
f
g
h
i
j
k
l
m
n
o
p
q
r
s
t
u
v
w
x
y
z
{
|
}
~
none
Value Character Value Character Value Character Value Character
Dec Hex Dec Hex Dec Hex Dec Hex
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
80
81
82
83
84
85
86
87
88
89
8A
8B
8C
8D
8E
8F
90
91
92
93
94
95
96
97
98
99
9A
9B
9C
9D
9E
9F
€
none
‚
ƒ
„
…
†
‡
ˆ
‰
Š
‹
Œ
none
Ž
none
none
‘
’
“
”
•
–
—
˜
™
š
›
œ
none
ž
Ÿ
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
A0
A1
A2
A3
A4
A5
A6
A7
A8
A9
AA
AB
AC
AD
AE
AF
B0
B1
B2
B3
B4
B5
B6
B7
B8
B9
BA
BB
BC
BD
BE
BF
nb Space
¡
¢
£
¤
¥
¦
§
¨
©
ª
«
¬
none
®
¯
°
±
²
³
´
µ
¶
·
¸
¹
º
»
¼
½
¾
¿
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
C0
C1
C2
C3
C4
C5
C6
C7
C8
C9
CA
CB
CC
CD
CE
CF
D0
D1
D2
D3
D4
D5
D6
D7
D8
D9
DA
DB
DC
DD
DE
DF
À
Á
Â
Ã
Ä
Å
Æ
Ç
È
É
Ê
Ë
Ì
Í
Î
Ï
Ð
Ñ
Ò
Ó
Ô
Õ
Ö
×
Ø
Ù
Ú
Û
Ü
Ý
ß
à
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
E0
E1
E2
E3
E4
E5
E6
E7
E8
E9
EA
EB
EC
ED
EE
EF
F0
F1
F2
F3
F4
F5
F6
F7
F8
F9
FA
FB
FC
FD
FE
FF
à
á
â
ã
ä
å
æ
ç
è
é
ê
ë
ì
í
î
ï
ð
ñ
ò
ó
ô
õ
ö
÷
ø
ù
ú
û
ü
ý
þ
ÿ
Extended ASCII Mode Translation Table
14
USB-ASC232 Configuration Program
The USB-ASC232 has programmable settings for adapting the
interface to the user’s application.
A program, “USBASC232.EXE” is included on the supplied CD.
Copy the entire contents of the CD into a folder on the (USB end)
target computer’s hard disk and run the .exe file from that folder.
There are a variety of protocol settings which can be selected from
the USBASC232.EXE configuration utility.
To create a configuration using the utility, first select the “Mode”
menu and choose ASCII, Extended ASCII, or Key Number Mode
based on the desired conversion mode.
Next, set the RS-232 communication parameters for the Baud
Rate, Number of Bits in the character, Parity, Number of Stop Bits,
and Handshaking mode.
The standard BAUD rates available are 2400, 4800, 9600,
14400, 19200, and 38400.
The number of bits in the character sent to the USB-ASC232 may
be 7 bits or 8 bits. NOTE: 8 bit characters are required for Ex-
tended ASCII and Key Number modes.
4
Value Character Value Character Value Character Value Character
Dec Hex Dec Hex Dec Hex Dec Hex
00
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
00
01
02
03
04
05
06
07
08
09
0A
0B
0C
0D
0E
0F
10
11
12
13
14
15
16
17
18
19
1A
1B
1C
1D
1E
1F
none
none
none
none
none
none
none
none
Backspace
Tab
none
none
none
Return
none
none
none
none
none
none
none
none
none
none
none
none
none
Esc
none
none
none
none
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
20
21
22
23
24
25
26
27
28
29
2A
2B
2C
2D
2E
2F
30
31
32
33
34
35
36
37
38
39
3A
3B
3C
3D
3E
3F
Space
!
“
#
$
%
&
‘
(
)
*
+
,
_
.
/
0
1
2
3
4
5
6
7
8
9
:
;
<
=
>
?
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
40
41
42
43
44
45
46
47
48
49
4A
4B
4C
4D
4E
4F
50
51
52
53
54
55
56
57
58
59
5A
5B
5C
5D
5E
5F
@
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
Q
R
S
T
U
V
W
X
Y
Z
[
\
]
^
-
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
60
61
62
63
64
65
66
67
68
69
6A
6B
6C
6D
6E
6F
70
71
72
73
74
75
76
77
78
79
7A
7B
7C
7D
7E
7F
`
a
b
c
d
e
f
g
h
i
j
k
l
m
n
o
p
q
r
s
t
u
v
w
x
y
z
{
|
}
~
none
ASCII Mode Translation Table
The ASCII mode table below lists the standard ASCII characters that
will produce a corresponding USB keystroke when received by the
USB-ASC232.
Extended ASCII Mode
The USB-ASC232 Extended ASCII Mode of operation allows for the
standard ASCII character set (character values 0x00 to 0x7F), in
addition to an extended ASCII character set (character values 0x80 to
0xFF). When an RS-232 byte is received in this mode, it produces a
USB keystroke on the PC which corresponds to the following table.
Parity may be set to “None”, “Odd”, or “Even”.
The number of stop bits may be set to 1 or 2 bits.
Handshaking may be set to “None”, “RTS/CTS”, or “Echo”.
When the handshaking is set to “None”, the computer sending the
information must be careful not to overflow the receiving buffer of
the USB-ASC232. The best way to do avoid the buffer overflow
in this mode is to delay 50msec after each byte is sent to the USB-
ASC232.
With handshaking set to “RTS/CTS”, the hardware controls the
flow of data between the computer sending the RS-232 data and
the USB-ASC232. This hardware handshaking prevents overflow
of the receiving buffer on the USB-ASC232 unit. When “RTS/CTS”
is used for handshaking, the DTR options for the serial port being
used on the computer sending the RTS-232 should be disabled.
The “Echo” setting means that the USB-ASC232 will send a one’s
complement response byte to each command. For instance, if a
value of 0x32 is sent to the USB-ASC232 serial port, it will reply
with a value of 0xCD in response. Use this handshaking mode as
a way to not only keep the buffer from overflowing, but is also a
confirmation of the value of the code that was received.
Note that in the “Echo” handshake mode, the response to the
0x7F request for LED status in Key Number Mode will be replied
with the status byte as outlined on page 8.
In “Echo” mode, the individual bytes of the mouse control packet
do not generate a reply. Only after the 4th and last byte of the
mouse packet has been received is an echo value of 0xFF returned
to indicate reception of the mouse packet.
15
Introduction to the USB-ASC232
The USB-ASC232 Keyboard and Mouse Emulator is a product designed
to allow RS-232 serial communication to produce USB keystroke and
mouse actions on a target computer.
The USB end of this device can be connected to any USB port that
supports a standard USB Keyboard and Mouse. No special drivers
are required.
The USB-ASC232 is configurable to allow for different standard BAUD
rates, stop bits, parity, handshaking, and mode of translation. Use the
supplied “USBASC232.EXE” program to configure the unit.
Translation Modes of the USB-ASC232
There are three specific translation modes in which the USB-ASC232
can be programmed to operate. Incoming RS-232 data can be
translated from ASCII Mode, Extended ASCII Mode, or Key Number
Mode. Each of these modes vary in the way incoming characters are
treated and their translation into USB keystrokes.
ASCII MODE (Default Mode)
The ASCII mode is the default factory setting for the mode of operation.
In this mode, printable ASCII characters received, which are each a
one byte value in the range of 0x00 to 0x7F (0 to 127 decimal), will
generate their corresponding USB keystroke on the computer where
the USB-ASC232 USB plug is connected. See the ASCII table on
the next page for a list of the characters which are recognized and
translated for the cable’s ASCII mode of operation.
Example: If a one byte value of 0x41 (decimal 65) is received in this
mode, a capital “A” character will be produced as a keystroke on the
computer at the USB end of the cable.
RS-232 characters received which are out of the 0x00 to 0x7f range
will be ignored in this mode.
3
Saving the Configuration to the USB-ASC232
Once the desired parameters have been set on the USBASC232
Configuration Utility Screen, it must be saved to the USB-ASC232 unit
to begin operation according to those settings.
Select the button “Save To USBASC232” to write the configuration to
the unit. Once the configuration has been written, the USB-ASC232
will begin immediately operating according to the loaded parameters.
The configuration may also be read from the USB-ASC232 unit by
selecting the button “Read From USB-ASC232”. The configuration
in the USB-ASC232 attached to the computer’s USB port will be read
into the configuration parameters on the screen.
Once a configuration has been created, it is recommended that it be
stored on the computer so that it may be recalled at a later time. Use
the “File” menu to perform saving and opening of configurations.
Saving the configuration to a file on the computer provides an easy
way to recall the same configuration to save into additional USB-
ASC232 units.
Custom USB-ASC232 Options
We offer special modifications to our standard USB-ASC232 unit to conform to your
exact specifications. Potential modifications include, but are not limited to: special
cable lengths, different gender DB9, RS-422, etc. Let us know if you have special
requirements. Please call or email with your specific custom needs.
16
Introduction to the USB-ASC232 3
Translation Modes of the USB-ASC232 3
ASCII Mode 3
Extended ASCII Mode 4
Key Number Number Mode 6
Additional Key Number Mode Commands 8
Key Number Mode Examples 9
Producing Mouse Action on the Target Computer 10
Mouse Packet Examples 12
Sending Serial Control Commands 13
USB-ASC232 Configuration Program
Serial Connector Pinout
14
17
Questions or Comments?
Please give us a call!
Toll Free
888-690-9080
or
www.hagstromelectronics.com
email: sales@hagstromelectronics.com
17 2
CONTENTS
Operating Voltage 5 Volts DC +/- 5%
(Powered from USB port)
Operating Current Less than 100 ma
Operating Temp. 0 to 70 Degrees C
PC Interface USB - Target Computer
RS-232 - Serial Source
Cable Length 6 feet
USB-ASC232 Specifications
PIN 2
TXD
PIN 3
RXD
PIN 5
GND
Serial Connector Pinout
The USB-ASC232 serial connection is a 9 pin female D type
connector. The pinout is designed such that it will attach directly
to a standard PC com port.
Pin 1 = Unused
Pin 2 = Serial Data out of USB-ASC232
Pin 3 = Serial Data into USB-ASC232
Pin 4 = Unused
Pin 5 = Logic Ground
Pin 6 = Unused
Pin 7 = CTS into USB-ASC232
Pin 8 = RTS out of USB-ASC232
Pin 9 = Unused Looking into connector face
PIN 7
CTS
PIN 8
RTS
Warranty
HAGSTROM ELECTRONICS, INC. warrants this
product against defects in material or workmanship for a
period of ONE YEAR from the original purchase date. We will
repair or replace (at our option) the returned defective unit
at no charge during this warranty period.
No responsibility is assumed for any special, incidental,
or consequential damage resulting from the use of or
inability to use this product. In no case is HAGSTROM
ELECTRONICS, INC. to be liable for any amount which
exceeds the purchase price of the unit, regardless of the
claim.
No other warranty, written or verbal, is authorized. This
warranty is applicable only to units sold in the United States.
Units sold outside the United States are covered by a similar
warranty.
Depending on the state in which you live, you may have additional rights.
Great care has been taken during the assembly, testing, and burn-in of
your USB-ASC232 to ensure its performance. If you have any questions,
please send us an email or give us a call. Support is available Monday
through Friday, 8:00 am to 5:00 pm (EST).
customer service email: [email protected]
Call Toll Free 888-690-9080, or (540) 465-4677
NOTICE: The USB-ASC232 product is designed to be used by
technically oriented computer users.
Thank you for purchasing the model USB-ASC232 Cable
HAGSTROM ELECTRONICS, INC.
is pleased that you have selected this product for your application.
This unit is may be used a variety of ways in order to meet your
specific requirements. Please take a few minutes to read this
manual before using your USB-ASC232.
If you have any questions about the use of the USB-ASC232
not covered in this manual, please contact us directly. We offer
toll free technical product support from 8:00am to 5:00pm M-F
Eastern Time 888-690-9080. You may also send an email to
We respond to all email requests within one business day.
USB-ASC232
ASCII RS-232 Controlled USB
Keyboard and Mouse Cable
User Manual
Toll Free 888-690-9080
Phone: (540) 465-4677 Fax: (540) 465-4678
Monday through Friday, 8:00 am to 5:00 pm (EST)
www.hagstromelectronics.com
1986 Junction Road, Strasburg, VA 22657
Copyright © 2020 HAGSTROM ELECTRONICS, INC.
V. 09.20
HAGSTROM
ELECTRONICS, INC.
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