PerkinElmer 550 User manual

MODEL-550
USER'S
MANUAL
PERKIN-ELMER
Terminals Division
Randolph Park West
Route 10 and Emery Avenue
Randolph, New Jersey 07801

MODEL 550
USER'S MANUAL
Publication 59300-0042-00
September 1978
This manual contains user information on the Model 550 CRT terminal. Its contents are
proprietary and may not be reproduced, in whole or in part, without written authorization
of the PERKIN-ELMER Terminals Division.

TABLE OF CONTENTS
Section 1 Introduction
1.1 General Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
1.2 General Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
1.3 Environmental Specifications ..................................................... 1-1
1.4 Physical Specifications ........................................................... 1-1
Section 2 Initial Check and Functional Test
2.1 Unpacking and Visual Inspection ................................................. 2-1
2.2 Environmental Requirements ..................................................... 2-1
2.3 Power Requirements ............................................................. 2-1
2.4 Functional Test Procedures ....................................................... 2-1
Section 3 Interfacing
3.1 Data Communications ............................................................ 3-1
3.2 Auxiliary Output Interface (optional) .............................................. 3-3
Section 4 Operations
4.1 Initial Setup ..................................................................... 4-1
4.2 Data Line Setup .................................................................. 4-1
4.3 Establishing Communications .................................................... 4-2
4.4 Operations ...................................................................... 4-2
4.5 Keyboard Functions .............................................................. 4-3
4.6 ASCII Control Functions .......................... : .............................. 4-5
4.7 Escape Code Sequences ......................................................... 4-8
Section 5 Maintenance
5.1 Cleaning ........................................................................ 5-1
5.2 Operator Checklist ............................................................... 5-1
5.3 Fuse Replacement ............................................................... 5-1
Figures
1-1 The Model 550 CRT . . . .. . . . .. . .. . .. . . .. . .. . . . . . .. . . .. . .. . . .. . .. . . . .. . . . . Frontispiece
3-1 20ma Current Loop Adapter . . . .. . .. . . .. . .. . . . . .. . . .. . . .. . . .. . . . .. . .. . . . . . . .. . . .. . 3-2
3-2 Current Loop Connections ....................................................... 3-3
4-1 Front Panel Switches ............................................................. 4-1
4-2 Transmission Modes ............................................................. 4-2
4-3 Model 550 Keyboard . . . .. . . .. . . .. . .. . . .. . . . . .. . . .. . .. . . .. . . .. . .. . . .. . . . . . . . .. . . . . 4-3
Tables
3-1 EIA Data Interface ............................................................... 3-1
3-2 Current Loop Interface ........................................................... 3-2
3-3 EIA Auxiliary Output Interface .................................................... 3-3
4-1 Keyboard Controls ............................................................... 4-4
4-2 Standard ASCII Code ............................................................ 4-5
4-3 Keyboard Codes ................................................................. 4-5
4-4 Escape Code Sequences ......................................................... 4-8
4-5 Cursor Addressing ............................................................... 4-9
5-1 Trouble Shooting ................................................................ 5-1

BRIGHTNESS
SLIDING PANEL &
ALTERNATE ACTION KEYS
RS232 CONNECTOR PRINTER PORT
TRANSPARENT MODE
ON/OFF
NUMERIC PAD
POWER CORD
MODE SWITCHES
Figure 1-1 Model 550 CRT

Section 1
INTRODUCTION
1.1 GENERAL DESCRIPTION
The PERKIN-ELMER Model 550 terminal is a low-cost, interactive teletypewriter replacement,
one of a family of PERKIN-ELMER CRT computer terminals. See Figure 1-1.
The hardware for the Model 550 is assembled from basic building blocks designed around a
proprietary LSI CRT controller chip.
1.2 GENERAL SPECIFICATIONS
The basicunitoperateson 115V, 60Hzforthedomesticmarketwith 1 OOV /115V/230V, 50/60Hzavail-
able for the international market. Communications are performed in a serial, asynchronous mode
using the EIA RS232C/CCITT V.24 interface or an optional 20ma current loop. Datatransmission
rate, parity selection, stop bit, and half and full duplex transmission modes are switch selectable.
Factory installed options are described under appropriate headings.
1.3 ENVIRONMENTAL SPECIFICATIONS
The terminal operates through an ambient temperature range of 0°C to 40°C with a maximum
relative humidity of 80% (non-condensing). When not in operation, it will withstand temperatures
ranging from -40°C to +65°C with a maximum relative humidity of 95% (non-condensing).
1.4 PHYSICAL SPECIFICATIONS
The Model 550 measures 14 inches high, 15 inches wide, and 19 inches deep: Itweighs 30 pounds
and has an off-white exterior with charcoal grey front. The standard keyboard contains high-
lighted control keys which facilitate high-speed operations.
Screen Format
Screen size
Screen capacity
Number of lines
Characters per line
Phosphor
Displayable characters
Character formation
Number of scans
Refresh rate
12 inches diagonal.
1920 characters.
24.
80.
P4 (white).
128 upper/lower case characters, numbers, punctuation, and
control characters.
5x9 characters in a 7x10 field.
10 per character.
50/60Hz (non-interlaced).
*35.5 x 38.1 x 48.3 cm; 13.6 Kg
1-1

Keyboard
Character code ASCII.
Keyboard layout ASCII, bit pairing.
Repeat key rate 12 cps.
Shadowed Numeric Pad 0-9, decimal point, comma, in standard calculator format.
Clear key To avoid accidental loss of data "Control" must be depressed at the
same time as "Clear."
Switch Format
Eleven baud rates
Stop bits
Transmission
Parity
Refresh rate
Video
Modem control
Current loop power
Transparent Mode
Factory Options
Keyboard
Universal power supply
Current loop cable
Peripheral Interface
Antiglare Screen
110, 200, 300, 600, 1200, 1800, 2400, 3600, 4800, 7200, and 9600 baud
One or two.
Full or half duplex.
Space, mark, even or odd.
50/60Hz.
White-on-black and black-on-white (inverse video).
The DTR lead to the modem is disabled when the terminal is in local
mode.
Switch selectable. +12V and -12V are supplied by the Model550 when
the current loop option is used. (see Table 3-2).
Switchable for display of control characters on the screen.
International keyboards are available in French, Swedish, Danish/
Norwegian, German, British, and Spanish character sets.
100V/115V/230V, 50/60 Hz, switch selectable
Switch selectable 20ma current loop for passive, active, or hybrid
connections.
Auxiliary output ("wye" type connection) direct connection to the
communications port, when enabled by the PRINT key.
Reduces reflection and glare.
1-2

Section 2
INITIAL CHECKOUT AND FUNCTIONAL TEST
2.1 UNPACKING AND VISUAL INSPECTION
All Model 550 terminals are thoroughly inspected at the factory for loose or missing hardware,
scratches and dents. After taking the terminal out of its box, inspect for any damage incurred
during shipment. Refer to the shipping papers to verify the presence of options.
If the shipping carton shows external damage and the unit does not perform properly, file a
claim with the shipping firm immediately and notify the PERKIN-ELMER Customer Service
Department. PERKIN-ELMER Technical Support Representatives and Customer Engineers
are available to provide consultation and assistance on request. A list of PERKIN-ELMER Sales
and Service offices is given at the end of this manual.
Retain packing material and container for any future repacking and shipment. Improper
repacking will void the warranty.
2.2 ENVIRONMENTAL REQUIREMENTS
See the detailed environmental requirements in Section 1.3.
The Model 550 terminal operates reliably in a typical office environment. Uncomfortably high
temperature coupled with low humidity may cause high voltage static discharges which can
impair performance. This evaluation should be made when selecting an installation site.
Place the Model 550 on a typewriter stand, low desk, or any other surface normally provided for
office typewriters.
2.3 POWER REQUIREMENTS
Proper power source and grounding are essential to optimum performance. Standard models are
equipped for 115V, ±10%. Wire a utility outlet directly to the main power panel for a "clean"
power source. Ensure that this line is free of other equipment, such as copying machines, calcu-
lators, electric typewriters, etc. These create electrical noise which may be transmitted through
power lines and, under certain conditions, cause a malfunction. The ground wire between the
terminal power connector and the main power panel ground must be uninterrupted.
2.4 FUNCTIONAL TEST PROCEDURES
To test all functions of the Model 550 prior to operations, proceed as follows:
1. Set the power switch ON, allowing 30 seconds for the CRT to warm up. The power switch is
on the right, above the key board.
2. Release the line key so that the terminal is in the local mode. The line key is on the keyboard,
above the alphanumeric keys.
3. Adjust the brightness of the display by adjusting the control dial. It is left, above the keyboard.
4. Set the duplex switch to half duplex operation. The duplex switch is mode switch 8, under the
sliding panel. Refer to page 4-1 for the location of this and other mode switches.
5. Depress each alphanumeric key in upper and lower case. Verify that the display is accurate.
6. Home the cursor by depressing the ESC and then upper case H keys.
7. Depress ESC and CTRL keys at the same time. The screen should fill with a scrolling display
of 95 characters plus the nondisplay character, DEL.
8. To terminate the scrolling display of the self-test, depress DEL and CTRL at the same time.
9. Familiarize yourself with the function keys by reading Section 4, Operations. Using the
Keyboard Control and Keyboard Code tables (Tables 4-1 and 4-3), verify that all keys work
as stated.
2-1

A final test may be performed with the Model 550 on-line in the full duplex mode if the host
processor can be programmed to be in the ECHOPLEX mode. Repeat the above test at the
desired baud rate to ~erify that the data line is operational. (Refer to Section 4 Operations, for
initial setup of the terminal.) ·
2-2

3.1 DATA COMMUNICATIONS
Section 3
INTERFACING
Theterminal transmits ASCII coded data in an asynchronousformat. See Table4-2. Each character
is preceded by a start bit and followed by one or two stop bits. The terminal has an
EAi RS232C interface and (when ordered), an optional 20ma current loop adapter. Those EIA
signals which apply to this class of terminal (asynchronous data communications) are
assigned to pins in accordance with EIA Specification RS232C for interfacing data communi-
cation equipment. Both the standard EIA circuit name and the circuit name used in Europe
(CCITT V.24) are shown in Table 3-1, EIA Data Interface.
Table 3-1. EIA Data Interface
25-Pln Male
Connector EIA RS232C
CCITT
Signal Name
1
AA
101
Chassis Ground
2
BA
103 Transmit Data
3 BB 104 Receive Data
6 cc 107 Data Set Ready
7 AB 102 Logic Ground
8 CF 109 Carrier On
9* --+12V
10* ---12V
19 --Printer Busy
20 CD 108.2 Data Terminal Ready
*Used on terminals with current loop option (switch selectable - See Figure 4-1).
The EIA Data Interface
Not all signals at this interface are required for most applications. Signal descriptions are
arranged from most used to least used.
Pin 1 - AA Chassis Ground, and Pin 7 - AB Logic Ground, should be carried in a cable to a
device such as a modem which is wired according to RS232C. These signals are tied internally.
The "primary channel" data lines, Pin 2 - BA Transmit Data, and Pin 3 - BB Received Data,
are the lines on which data go to and from the terminal.
The signals, Pin 6- CC Data Set Ready, and Pin 8- CF CarrierOn, are notused by theModel550.
When mode switch 9 is OFF, the line key, on the keyboard, controls Data Terminal Ready.
When the terminal is on-line, Data Terminal Ready is high. If the terminal is switched to local
(off-line), Data Terminal Ready is switched low. When Switch 9 is ON, Data Terminal Ready
is held at a constant high.
If an auxiliary output interface is used, then when the printer generates a busy signal on pin 5
of its auxiliary port, the signal is sent to the host on pin 19 of the EIA Data Interface.
3-1

The Current Loop Interface (optional)
The current loop cable converter board forms an integral part of the cable. The board converts
the RS232C signals into 20ma current loop levels. The signals generated by the interface are
listed in Table 3-2.
Table 3-2. Current Loop Interface
Signal 15-Pin Male
Name Connector
Logic ground
15
TDU* 7
Receive(+)
11
Receive (-)
12
Send (+) 9
Send (-)
10
Chassis ground 1
The current loop interface uses optoisolators and can operate at any speed up to 9600 baud,
depending on line length and type.
Two techniques for using the current loop are:
1. The terminal supplies the 20ma current for the loop (active).
2. The user's device supplies the 20ma current for the loop (passive).
Frequently, a hybrid of the two is used, e.g., the user provides the 20ma to the terminal but
expects "contact closure" outputs from the terminal. (Most teletypewriters accept a loop
current and provide "contact closure" outputs.) The adapter box on the optional current loop
cable permits the setting of switches (Passive/Active) on both the send and receive current
loops. See Figure 3-1.
Figure 3-1. 20ma Current Loop Adapter
*Busy signal used by Perkin-Elmer processor systems.
3-2

Figure 3-2 Current Loop Connections
550 Supplies Loop Current
Switc~ in Re?~ive IReceive (+) o+ Host
Active pos1t1on. Receive (-) ---------
0_
Switch in Send !Send (+) O+
A . . Host
ct1ve position Send (-) o-
Host Supplies Loop Current
Receive (+)~---------0+
Host Supplied 20ma output.
Receive (-) o-·
Send (+) O+
Host Supplied 20ma input.
Send (-) 0-
3.2 AUXILIARY OUTPUT INTERFACE (Optional)
A local output device, such as a printer, can be connected to the Model 550 via the auxiliary
output interface port located on the rear panel of the terminal. The port is unidirectional and
is intended to interface serial devices adhering to EIA standards.
Depressing the latching print key connects serial data from the host computer to the
auxiliary output interface port via a "wye" connection between the communications port
and this port.
Printers which generate busy characters (DC1/DC3; DC2/DC4), are received on pin 2 of the
auxiliary interface. They are ORed with the CRT keyboard data.
RS232C Interface
Table 3-3 lists the pin connections and signal names used on the RS232C auxiliary output
interface.
Table 3-3. EIA Auxiliary Output Interface
25-Pin Female Signal Name
1 Chassis ground
2 Printer Transmit Data
3 Printer Receive Data
5 Printer Busy
6 Data Set Ready (+12V)
7 Logic Ground
8 Carrier On
(-12V)

4.1 INITIAL SETUP
Section 4
OPERATIONS
Before starting operations, the following procedures should be performed:
1. Set the power switch to ON. Allow 30 seconds for warm up.
2. Place the terminal in the local mode by releasing the line key (undepressed).
Adjust the brightness control to the desired comfort level.
3. Set full or half duplex, switch 8,for either full duplex (FOX) or half duplex (HDX) operation
as required.
4. Type a message and verify that it is correctly displayed on the CRT screen.
4.2 DATA LINE SETUP
Switches are under the sliding front panel above the keyboard. (See Figure 4-1)
1. Set the baud rate switch to the transmission rate of the host computer.
2. Set the stop bits to one or two.
3. Set the parity, switches 1 and 2, to the parity state required by the host computer.
4. Set refresh rate, switch 4 (50 or 60 Hz).
5. Set the DTR, switch 9, to the required protocol.
6. Enable the +12V and -12V switches (6 and 7 respectively), if the current loop cable is
connected.
7. Set the Passive/Active switches on the current loop adapter cable as required (refer
to Table 3-2).
8. Depress the line key on the keyboard.
Figure 4-1. Front Panel Switches
Parity Mode
Switch 1 2 Switch 3 4 5 6* 7* 8 9
Odd OFF OFF ON 1-stop 50 Hz INV. +12V
-12V
HDX DTR high
Even OFF ON video
Mark ON OFF OFF 2-stop 60 Hz STD. open open
FOX LINE switch
Space ON ON controlled DTR
*Used with the current loop option.
4-1

4.3 ESTABLISHING COMMUNICATIONS
The next step depends upon the communications link used by the host computer. If the host
computer is accessed via private wire or direct cable connections, the Model 550 is ready
for operation. If the Model 550 is connected via switched telephone lines, the computer must
be dialed to establish the connection.
4.4 OPERATIONS
Operation of the Model 550 is controlled by the computer and/or the keyboard, d~pending
on the transmission mode. Figure 4-2 depicts the various selectable modes of operations.
On-line operations may take place in either full or half duplex mode. In the full duplex mode,
data transmitted via the keyboard do not appear on the CRT unless the host computer is
programmed to echo the characters (ECHOPLEX).
In the half duplex mode, ECHOPLEX is not required since a direct tie to the electronics is
completed via the duplex switch. Queries and acknowledgements from both
the host computer and the keyboard will be displayed in the conventional manner. However,
if the keyboard and computer generate data simultaneously, the display will show intermixed
characters.
Note that in local mode, no data are transmitted over the lines. Keyboard input causes the
appropriate action to take place directly on the display. In all cases, display memory will
store and display all displayable input characters. Non-displayable characters are not stored
in the display memory unless preceded by an ESC.
In the transparent mode, all received characters are stored in display memory. Control
characters such as CR, LF, etc., are displayed but not executed.
In this mode only, the display provides automatic CR/LF at the end of each line and
scrolls at the end of the page.
FROM CPU
_J
c
u
9
~TO CPU e
Figure 4-2. Transmission Modes
PRINT
HALF
FULL
DUPLEX
4-2
PRINTER
DISPLAY
ELECTRONICS

4.5 KEYBOARD FUNCTIONS
The terminal keyboard (Figure 4-3) is separated into two basic groups of keys, alpha-
numeric keys used to enter data, and function keys used in peripheral control, to erase screen,
etc. All the alphanumeric keys generate ASCII code which, depending on the transmission
mode, is immediately transmitted and/or stored in terminal memory. The repeat key feature
of the Model 550 causes a repetition rate of 12 cps after any key is held down in con-
junction with it.
Figure 4-3. Model 550 Keyboard
The following keyboard description (Table 4-1), lists each key and its control function. An
asterisk (*) designates alternate action switches, double asterisks (**) designate momentary
action switches, and an "at" sign (@) designates ASCII character generation.
4-3

Item Control Key
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
LINE
U/C
PRINT
NUM ONLY
REPEAT
CLEAR
ESC
TAB
BACK
SPACE
DEL
LINE
FEED
RETURN
CTRL
SHIFT
LOCK
SHIFT
BREAK
Space Bar
and
Character
Keys
*Alternate
** Momentary
@ASCII
Table 4-1. Keyboard Controls
Function
*When set, places terminal on-line. When released (off-line), and
full/half duplex switch is in half duplex, terminal displays only
data entered via the keyboard. No data are received ortransmitted
via the communications lines.
*Lower case alpha characters are converted to upper case, plus
the following:. to@, { to [, I to \ , } to J and -. to A
Conversion takes place only to characters entered from the
keyboard.
*Enables the auxiliary port; on-line data are routed via a "wye"
connection from the communications port to the auxiliary
output port.
*When set, enables the calculator formatted keyboard section
for quick numeric entries.
**Used in conjunction with other keys to provide an instant and
continuous repetition of the depressed key. Repeat rate is
12 cps.
**When depressed simultaneously with CTRL, display memory
is cleared and cursor goes to Home.
@**(EC) Escape Key used in conjunction with other keys to enable
specific functions.
@**(HT) Horizontal tab used to move the cursor to the next tab
position. If the cursor is at the end of the line, it will move to the
first position of the next line.
@**(BS) Moves the cursor to the left one position. The cursor will
not move if a backspace is attempted at Home. If the.cursor is
in position one of any line _(except line one), it will "wrap back"
to position 80 of the previous line when backspace is attempted.
@**Generates an ASCII delete character which is stored only
if preceded by ESC.
@**(LF) Used to move the cursor down one line. On the 24th line
the display is moved up one line, causing line one to scroll
off the display.
@**(CR) Returns the cursor to the first position of the current line.
**Control key used in conjunction with other keys to enable
specific functions.
*Used to maintain the shift key in the depressed state.
**Permits the entry of all the upper case characters depicted on the
keyboard.
**Presents the communications line with a space (break) for as
long as the key is depressed. It has no effect when the terminal is
in local mode.
@**Writes a character at the current position and moves the cursor
one position to the right. The cursor will stop at position 80.
Any additional entries will overwrite at position 80.
4-4

4.6 ASCII CONTROL FUNCTIONS
The American Standard Code for Information Interchange (ASCII). provides a set of 32
transmittable characters which are keyboard generated using a simultaneously depressed
CTRL key and a character key (see Tables 4-1 and 4-2). The codes are functionally group~d
as follows:
Communication control characters -Functional characters which control or facilitate
transmission of information over communications networks.
Format effector codes -Functional characters which control the layout or position of
information in printing or display devices.
Information separator codes -A group of four characters which are used in a graded
order that serves to separate and qualify information.
Table 4-2. ASCII Coding Chart
rCOMMUNICATION
PRINTABLE
CODES
CHARACTERS
b1
0 0 0 0 1 1 1 1
b5
0 0 1 1 0 0 1 1
bs 0 1 0 1 0 1 0 1
a.
b4
bJ b2
bl
r--co~
\ i i
.i
i
ROW
0 , 2 3 4 5 6 7
0 0 0 0 0
NUL
OLE
SP
0 (al
p p
0 0 0 1 1
SOH DCl ! 1 A a a q
d 0 1 0 2
STX
DC2
" 2 B R b r
0 0 1 1 3
ETX
DC3
# 3 c s c s
0 1 0 0 4
EOT
DC4
$ 4 D T d t
0 1 0 1 5
ENQ
NAK % 5 E u e u
0 1 1 0 6
ACK SYN
& 6 F v f v
0 1 1 1 7 BEL
ETB
7 G w g w
1 0 0 0 8
BS
CAN
( 8 H x h
)(
1 0 0 1 9
HT
EM
) 9 I y i y
1 0 1 0
10 LF
SUB
. : J z j z
1 0 1 1 11 VT
ESC
+ K ( k {
1 1 0 0 12
FF FS
< L \ I I
I
1
.1
0 1 13 CR GS
-= M J m }
1 1 1 0 14
so RS
> N
~
n
,..,._,,
1 1 1 1
15 SI us
I ? 0 -0
DEL
Table 4-3. Keyboard Codes
CTRL&KEY CODE FUNCTION
@ *NUL (Null) All-zeros character which can be used to accomplish time and
media fill.
A *SOH (Start
of
Communicationscontrol character used atthe beginning of sequence
Heading)
of characters constituting machine-sensible address or routing
information.
B *STX (Start
of Communications control character which precedes the transmission
Text)
of characters started by STX.
*Ignored when received by the Model 550.
4-5

Table 4-3. Keyboard Codes (Continued)
CTRL & KEY CODE FUNCTION
c *ETX (End of
Communications control character used to terminate a sequence
Text) begun with STX.
D *EQT (End of
Communications control character used to indicate conclusion
Transmission) of message transmission.
E *ENO (Enquiry) Communications control character used
as a request for a response
from remote station.
F *ACK Communications control character transmitted
by the receiver as an
(Acknowledge) affirmative response to sender.
G *BEL (Bell) Character used to cause an audible alarm at a remote terminal.
H
BS (Backspace) Format effector causing the cursor to move one space backward
on same line.
I
HT (Horizontal Format effector causing the cursor to move to the next-in-series
Tabulation) of predetermined positions along the line. Fixed tab stops are in every
eighth position.
J LF (Line Feed) Format effector causing the cursor to advance
to the next line.
K *VT (Vertical Format effector causing movement
of paper to first predetermined
Tabulation) line on next form
or page.
L
FF (Form Feed) Treated by the Model 550
as the equivalent to line feed.
M CR (Carriage Format effector which causes cursor
to position itself at the first
Return) position
of the line.
N *SO (Shift Out) Code used to indicate that code combinations which
follow will be
interpreted as outside of the character set of standard ASCII Code
until an SI character is reached.
0 *SI (Shift In) Code used
to indicate that code combinations which follow will
conform to codes listed on the standard ASCII Code Chart
p *DLE (Data Link Communications control character which will change the meaning
Escape)
of a limited number of continuously following characters.
*Ignored when received by the Model 550.
4-6

CTRL & KEY CODE
*Q (=DC1)
*R (=DC2)
*S (=DC3)
*T (=DC4)
u
v
*NAK (Negative
Acknowledge-
ment)
*SYN (Synchro-
nous Idle)
Table 4-3 Continued
FUNCTION
Device controls, used for control of auxiliary devices associated with
communications systems, especially switching devices on or off.
Communications control character transmitted by the receiving
station as negative response to the sending station.
Communications control character used by a synchronous trans-
mission system.
,___ ____________________________________ ,_
w *ETB (End
of
Transmission
Block)
Communications control character used to indicate the end of block
data.
1--------------------------------------~-
x
y
z
I
]
"
-
No CTRL
Key
*CAN (Cancel)
*EM (End of
Medium)
*SUB
(Substitute)
ESC (Escape)
*FS (File
Separator)
*GS (Group
Separator)
*RS (Record
Separator)
*US (Unit
Separator)
DEL (Delete)
Control character used to indicate that the data with which it is
sent is in error or is to be disregarded.
Control character used to indicatethe physical end of medium, or the
end of the unwanted portion of information recorded on the medium.
Character used for substitution of acharacter that is determined to be
invalid or in error.
Control character used to provide code extension. The Escape
character itself is a prefix affecting the interpretation of a limited
number of suffix characters.
Information separators used within data in an optional fashion. FS
is most inclusive. US is least inclusive.
Character used primarily for time and media fill.
'*Ignored when received by the Model 550.
4-7

4.7 ESCAPE CODE SEQUENCES
The Model 550 offers, as standard, use of the ESC key plus a character key or keys to effect
an escape code sequence. Escape code sequencing permits the expansion of the ASCII code
to include controls for cursor positioning, direct cursor addressing, and display clearing.
Unlike the ASCII control functions, these functions are initiated by depressing and releasing
the ESC key followed by the character key(s). The terminal offers the following escape code
sequences:
Table 4-4. Escape Code Sequences
Code* Action
ESCA
Cursor up.
Moves cursor up by one line. If in line one, cursor will wrap around to line 24.
ESC B Cursor down.
Moves cursor down by one line. If in line 24, will move display up by one line.
ESCC
Cursor right.
Moves cursor one position to the right. When cursor is moved beyond
position 80 the cursor will wrap around to position 1 of the following line.
ESC D Cursor left.
Moves cursor one position to the left. When cursor is moved beyond
position 1 the cursor will wrap around to position 80 of the previous line.
The code is ignored if the cursor is at the Home position.
ESCH
Cursor home.
Moves cursor to position 1, line 1 (Home).
ESC X Direct cursor address -line position.
character Moves cursor vertically to any line
as specified by the character following
"X", as shown in Table 4-5. The code is ignored if it exceeds 24 lines.
ESC Y Direct cursor address -character position.
character Moves cursor horizontally
to any position on a line. The character
following "Y" specifies the character position as specified in Table 4-4.
ESC K Clear all.
Will clear display memory to spaces and home the cursor. ESC K needs
20ms to refresh. Thus, the programmer should insert sufficient nulls
as filler data (20 at 9600 baud).
ESC I Clear line.
Will clear the line (reset to spaces), starting with the present position of the
cursor through the end of the line. ESC I needs 20ms to refresh. Thus,
the programmershould insertsufficientnulls as fillerdata (20at9600 baud).
ESC (followed by a non-ESC character).
ASCII characters other than A, B, C, D, H, X, Y, K, and I are stored in the
display memory as data.
ESC ESC
When asecond ESC code follows an ESC, the second is displayed but is
not used to generate any ESC code sequences with following characters.
*Note that ESC combinations are uppercase.
4-8