B&B Electronics 232BSS4 User manual

Documentation Number 232BSS41202 Manual Cover Page
B&B Electronics Mfg Co Inc – 707 Dayton Rd - PO Box 10 0 - Ottawa IL 61350 - Ph 815- 33-5100 - Fax [phone]
B&B Electronics Ltd – Westlink Commercial Park – Oranmore, Galway, Ireland – Ph [phone] – Fax [phone]
Buffered Smart Switch CE
Model 232BSS4
Documentation Number 232BSS41202
International Headquarters
B&B Electronics Mfg. Co. Inc.
707 Dayton Road -- P.O. Box 1040 -- Ottawa, IL 61350 USA
Phone [phone] -- General Fax [phone]
Home Page: www.bb-elec.com
Sales e-mail: [email protected] -- Fax [phone]
Technical Support e-mail: [email protected] -- Fax [phone]
European Headquarters
B&B Electronics Ltd.
Westlink Commercial Park, Oranmore, Co. Galway, Ireland
Phone [phone] -- Fax [phone]
Home Page: www.bb-europe.com
Sales e-mail: [email protected]
Technical Support e-mail: [email protected]
1999 B&B Electronics -- Revised May 2002
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Documentation Number 232BSS41202 Manual Table of Contents i
B&B Electronics Mfg Co Inc – 707 Dayton Rd - PO Box 10 0 - Ottawa IL 61350 - Ph 815- 33-5100 - Fax [phone]
B&B Electronics Ltd – Westlink Commercial Park – Oranmore, Galway, Ireland – Ph [phone] – Fax [phone]
Table of Contents
Chapter 1: INTRODUCTION......................................1
Specifications....................................................................................2
Default Parameters...........................................................................2
Checklist...........................................................................................3
Chapter 2: OPERATION................................................4
Symbols and Conventions................................................................4
LED Indicators..................................................................................4
Port Configurations...........................................................................5
Smart Switch Only Mode..................................................................6
Auto Select/Smart Switch Mode.....................................................13
Using the 232BSS4 as a Buffered Splitter/Combiner.....................15
Back to Back Operation (mux/demux)............................................16
Cascading Multiple Switches..........................................................17
Chapter 3: PORT CONNECTIONS.......................20
DTE/DCE Explanation....................................................................20
Chapter 4: SETUP SOFTWARE.............................22
Introduction.....................................................................................22
Connection......................................................................................22
Software Installation .......................................................................23
Software Uninstall...........................................................................23
Setup Tutorial .................................................................................24
Appendix A: ASCII Character Codes......................................A-1
Appendix B: Cable Charts ........................................................B-1
Chart B.1. DTE (PC) DB25 Connector to Master Port..................B-1
Chart B.2. DTE (PC) DB9 Connector to Master Port....................B-1
Chart B.3. DCE (Modem) DB25 Connector to Master Port ..........B-2
Chart B.4. DCE (Modem) DB9 Connector to Master Port ............B-2
Chart B.5. Ports A-D (DTE) to DTE (PC) DB25 Connector..........B-2
Chart B.6. Ports A-D (DTE) to DTE (PC) DB9 Connector............B-3
Chart B.7. Ports A-D (DTE) to DCE (Modem) DB25 Connector...B-3
Chart B.8. Ports A-D (DTE) to DCE (Modem) DB9 Connector.....B-3
Appendix C: Block Diagram .....................................................C-1
Appendix D: Declaration of Conformity ..................................D-1
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Documentation Number 232BSS41202 Manual 1
B&B Electronics Mfg Co Inc – 707 Dayton Rd - PO Box 10 0 - Ottawa IL 61350 - Ph 815- 33-5100 - Fax [phone]
B&B Electronics Ltd – Westlink Commercial Park – Oranmore, Galway, Ireland – Ph [phone] – Fax [phone]
Chapter 1: INTRODUCTION
The 232BSS4 provides communications to four devices from one
serial port. Each port uses a dedicated UART and includes an 8K
byte transmit buffer and an 8K byte receive buffer (16K bytes total).
Each port can be independently configured for data rate, data
format, and protocol. The Master port can send and receive data
from one of the Slave ports while the other Slave ports continue to
buffer data. The Master device can also broadcast the same
message to two or more Slave ports at once.
The 232BSS4 can be configured to send data automatically to
the Master port from each of the Slave ports when data is present
with an optional preamble identifying the port. It can also provide
two-way communications between the Master port and one Slave
port at a time. Switching and control is done through user-defined
three or four character command strings. All control sequences are
removed from the data stream, making the switch transparent to the
Slave devices. The PC setup software provided walks the user
through all possible parameters.
Switches can be cascaded to expand the 232BSS4 to more than
four ports. Two units can also be used back-to-back to provide
automatic connection between devices over a single data channel.
LEDs on the 232BSS4 indicate when the unit is powered up and
which port is selected to send data to the Master port.
PORT D
232BSS4
PORT A PORT B PORT C
MASTER PORT
BUFFERED SMART SWITCH
+12 VDC
POWER
OTTAWA IL 61350 USA
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Documentation Number 232BSS41202 Manual
B&B Electronics Mfg Co Inc – 707 Dayton Rd - PO Box 10 0 - Ottawa IL 61350 - Ph 815- 33-5100 - Fax [phone]
B&B Electronics Ltd – Westlink Commercial Park – Oranmore, Galway, Ireland – Ph [phone] – Fax [phone]
2
Specifications
Model: 232BSS4
Interface: RS-232 asynchronous
Data Format: 7 or 8 data bits, even, odd, or no parity
(Master does not support 7 data bits with
no parity)
1stopbit(fixed)
Data Rate: 1200 to 115.2 kbps
Flow Control: Hardware(RTS/CTS) or None
Power Requirements: +10to+15VDC@60mAmax.
Power Connector: 2.5 mm phone jack (+ tip)
Recommended Supply: B&B Model 232PS (Sold separately)
Operating Temperature: 0º to 70º C
Data Connectors: Master DB25 female (DCE)
Slaves DB9 male x 4 (DTE)
Dimensions: 7.5 x 4.6 x 1.2 in. (19.0 x 11.7 x 3.0 cm)
Setup Software: PC compatible,
Windows 95/98/NT/2000/XP
Supplied Accessories: CDROM with Setup Program
Instruction Manual
Default Parameters
When shipped, the 232BSS4 comes set up for the following
parameters:
Auto Select mode OFF
DTR NOT required to accept commands
THREE character command
Char1 = ESC (Decimal 27)
Char2 = STX (Decimal 2)
Char3 = “0” (Not Used)
Port Time = 1,000mS (not used)
Inactivity Time = 500mS (not used)
All ports 9600 Baud
All ports 8 Data Bits
All ports No Parity
All ports No Hardware Handshake required
Ports A-D No preamble
Port A selected to Transmit & Receive on Power-up
Refer to the following sections of the manual for what each of
these parameters means and how they can be changed.
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Documentation Number 232BSS41202 Manual 3
B&B Electronics Mfg Co Inc – 707 Dayton Rd - PO Box 10 0 - Ottawa IL 61350 - Ph 815- 33-5100 - Fax [phone]
B&B Electronics Ltd – Westlink Commercial Park – Oranmore, Galway, Ireland – Ph [phone] – Fax [phone]
Checklist
Examine the shipping carton and contents for physical damage.
If damage is found, file a claim with the shipper immediately.
The following equipment should be in the shipping carton:
1. RS-232 Buffered Smart Switch model 232BSS4
2. Instruction Manual
3. (2) 3.5" floppy disks
If any of the items above are not in the shipping carton contact
the shipper immediately.
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Documentation Number 232BSS41202 Manual
B&B Electronics Mfg Co Inc – 707 Dayton Rd - PO Box 10 0 - Ottawa IL 61350 - Ph 815- 33-5100 - Fax [phone]
B&B Electronics Ltd – Westlink Commercial Park – Oranmore, Galway, Ireland – Ph [phone] – Fax [phone]
4
Chapter 2: OPERATION
Symbols and Conventions
Throughout this chapter of the manual, the following symbols and
conventions will be used to clarify what type of data we are
addressing.
• Items enclosed in {brackets} will denote one byte.
• A character in “quotes” will normally denote a printable ASCII
character. A byte described in ALL CAPS is the ASCII
description of a non-printable character. The abbreviation
dec will denote a decimal value. The lower case letter h will
be used to show a Hex value.
• Items in
italics are optional items only used in certain
configurations. The instances when these items are required
will be explained in the text.
LED Indicators
The 232BSS4 has five LED indicators. The first, labeled “+12
VDC POWER” indicates that power is applied to the switch. The
other four, labeled “PORT A” to “PORT D” indicate which Slave port
is currently selected to transmit to the Master.
In Smart Switch Only mode, the port LEDs indicate which port
was selected through the Select Port command. In Auto Select
mode, the port LEDs indicate which port is currently sending to the
Master. No indication is provided to display which Slave port is
currently receiving from the Master.
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Documentation Number 232BSS41202 Manual 5
B&B Electronics Mfg Co Inc – 707 Dayton Rd - PO Box 10 0 - Ottawa IL 61350 - Ph 815- 33-5100 - Fax [phone]
B&B Electronics Ltd – Westlink Commercial Park – Oranmore, Galway, Ireland – Ph [phone] – Fax [phone]
Port Configurations
The 232BSS4 provides a dedicated UART to all five ports. This
allows any port to be individually configured for baud rate, number of
data bits, parity, and hardware (RTS/CTS) handshaking.
Configuration of all the ports is done through the setup software.
Baud Rate:
Each port is configurable for the following baud rates:
1200
2400
4800
9600
19.2K
38.4K
57.6K
or 115.2 kbps
Data Bits:
Each port can be configured for Seven or Eight data bits.
Note: If the Master and Slaves are set up differently, the port set
for Seven data bits cannot transmit the eighth bit.
Parity:Each port can be configured for Even, Odd, or No parity.
Because the Master port uses a slightly different UART, it is not
capable of receiving only seven bits, thus seven data bits with no
parity is not allowed on the Master port. All other configurations
are possible.
Stop bits:
Each port uses 1 stop bit. This value is currently fixed and
can not be changed in the setup software.
Hardware(RTS/CTS) Handshaking:
Each port can be configured to hold data until its input
handshake line goes high. On the Master port, pin four (RTS)
would have to be held high by the host device in order for the
232BSS4 to send data. On the Slaves, pin eight (CTS) needs to
be held high by the Slave device for the 232BSS4 to send data.
The connected devices can prevent data from being sent from
the 232BSS4 by holding their corresponding handshake lines
low.
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Documentation Number 232BSS41202 Manual
B&B Electronics Mfg Co Inc – 707 Dayton Rd - PO Box 10 0 - Ottawa IL 61350 - Ph 815- 33-5100 - Fax [phone]
B&B Electronics Ltd – Westlink Commercial Park – Oranmore, Galway, Ireland – Ph [phone] – Fax [phone]
6
Smart Switch Only Mode
Description:
Smart Switch Only mode is used when the host device connected
to the Master port initiates all communications with the Slave
devices. To use the 232BSS4 as a Smart Switch Only, Auto Select
is left unchecked in the setup software.
In Smart Switch Only mode, the 232BSS4 is constantly looking
for a command sequence by monitoring the data that is being
received on the Master port from the host device. This command
can tell the 232BSS4 to connect the Master port to a single Slave
port, send data to one or more Slave ports at once, discontinue
communications with all Slave ports, or ignore commands for a
specific length of time.
All command characters are buffered until the full command
sequence is received. If the 232BSS4 recognizes the data stream as
a command sequence, the sequence is not passed through the
switch.
Options:
Initial Connections:
Upon power-up, the 232BSS4 can be initialized to allow the
Master access to any of the Slave ports without any commands
sent. The Master to Slave and Slave to Master initialization are
each independently configurable through the setup software. The
Master can also be set to broadcast to any or all of the Slave
ports on power-up. If no ports are selected to be initialized on
power-up, the 232BSS4 will wait for a switching command before
allowing the Master access to any of the Slaves.
3 or 4 Character Command:
The 232BSS4 commands can be set to be either three or four
characters long. The first two or three characters can be
programmed to any value through the setup software. The third
or fourth character is the actual command.
Thus the command sequence would look like:
{Char1}{Char2}
{Char3} {Command Character}
Char1-3 would be defined by the user through the setup
software.
Char3 would only be sent if the 232BSS4 was set up for a four
character command.
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Documentation Number 232BSS41202 Manual 7
B&B Electronics Mfg Co Inc – 707 Dayton Rd - PO Box 10 0 - Ottawa IL 61350 - Ph 815- 33-5100 - Fax [phone]
B&B Electronics Ltd – Westlink Commercial Park – Oranmore, Galway, Ireland – Ph [phone] – Fax [phone]
Command Summary:
Three Character Command Format:
Char1 Char2 Command Char
Control Char
Control Char is only needed for Tx Only, Clear Buffer, and Ignore
Commands
Four Character Command Format:
Char1 Char2 Char3 Command Char
Control Char
Control Char is only needed for Tx Only, Clear Buffer, and Ignore
Commands
Table 2.1 - 232BSS4 Command Summary
Function Command
Char. Control Char. Comments
Select Port A Tx & Rx “A” None Switching Command
Select Port B Tx & Rx “B” None Switching Command
Select Port C Tx & Rx “C” None Switching Command
Select Port D Tx & Rx “D” None Switching Command
Deselect All Ports EOT None Switching Command
Tx Only to Specific
Ports “S” Dec 0 to 15 Use to Broadcast
Clear Buffer on
Specific Ports “X” Dec 0 to 15 Clear the Receive Buffer
Ignore Commands “T” “0” to “9” Sets Timer Value
Values in quotes “” are ASCII characters.
Dec. is an abbreviation for decimal value.
Command Explanation:
Where applicable, this section will provide an example of how to
create the command strings in Visual Basic. Other programming
languages may require a slightly different syntax, but the examples
given should provide enough information to port to other languages.
For our examples, we will use the default settings of the switch:
• 3 Character Command Sequence
• Character 1 set to ASCII ESC character (Decimal 27)
• Character 2 set to ASCII STX character (Decimal 2)
If you choose to use a four character command sequence, just
add another character between the second programmable character
and the command character in the command string.
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Documentation Number 232BSS41202 Manual
B&B Electronics Mfg Co Inc – 707 Dayton Rd - PO Box 10 0 - Ottawa IL 61350 - Ph 815- 33-5100 - Fax [phone]
B&B Electronics Ltd – Westlink Commercial Park – Oranmore, Galway, Ireland – Ph [phone] – Fax [phone]
8
Commands:
Select Port A to transmit and receive –“A”
Select Port B to transmit and receive –“B”
Select Port C to transmit and receive –“C”
Select Port D to transmit and receive –“D”
The Select Port commands turn on the selected port for both
transmit and receive operations. Once the command is received
by the switch, any data that had been buffered from the selected
Slave device will be sent to the Master. Any data received on the
Master port that is not a valid command sequence will be passed
to the selected Slave port until another command is received.
For instance, to send and receive data from port B, send:
{Char1}{Char2}
{Char3} ”B”
VB Example:
SwitchB$= CHR$(27) & CHR$(2) & “B”
Turn Off all selected ports – ASCII EOT character (decimal 4)
The Turn Off command deselects all ports. No ports will
transmit or receive to/from the Master port until another
command is received by the Master port.
The full command sequence to disable all ports is:
{Char1}{Char2}
{Char3} EOT
VB Example:
OFF$= CHR$(27) & CHR$(2) & CHR$(4)
Send Only to specific ports – “S” + one control byte specifying which
ports to send.
The Send Only command will tell the 232BSS4 which Slave
ports to send the following data to. This command can be used to
broadcast data to more than one port at a time. The Slave port
that is sending to the Master is not affected.
The lowest four bits of the control byte tell the 232BSS4 which
ports should receive the following data. Bit 0 represents port A,
Bit 1 represents port B, Bit 2 represents port C, and Bit 3
represents port D. In decimal, this is represents a value of 1, 2, 4,
and 8 respectively. To turn on more than one port, the decimal
equivalents of each port are added together to give the final byte.
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