PINOUTS
DB-25 Connector Signal Name
1 ........... Shield Ground
2 ........... Transmit Data (Tx)
3 ........... Receive Data (Rx)
4 ........... Request To Send (RTS)
5 ........... Clear To Send (CTS)
6 ........... Data Set Ready (DSR)
7 ........... Signal Ground
8 ........... Data Carrier Detect (DCD)
20 ........... Data Terminal Ready (DTR)
NOTE:
Serial Card 3 has a modem eliminator button, when this button is "in" the
above pin outs are correct. If the button is "out" this has the effect of
a modem eliminator cable being installed.
Apple III Port C: RS-232-C Serial Interface & Serial Card 3 "Driver"
DATA CONFIGURATION BLOCKS
The following table explains how to configure the driver for the RS232 port
using the System Configuration Program in the Apple III System Utilities
(remember, to set the slot number).
DCB $00 = BAUD RATE
For BAUD RATE - Set $00 DCB to:
110 - $03
134.5 - $04
300 - $06
600 - $07
1200 - $08
1800 - $09
2400 - $0A
4800 - $0C
9600 - $0E
DCB $01 = DATA FORMAT
For Bits Parity - Set $01 DCB to:
Bits Parity
8 none - $00
7 odd - $22
7 even - $26
7 MARK - $2A
7 SPACE - $2E
6 odd - $42
6 even - $46
6 MARK - $4A
6 SPACE - $4E
DCB $02 thru $04 = PRINTER DELAYS
Using this driver to connect to a printer may require that you set the delay
time then observe the printer while it actually performs the function you
want it to delay after (i.e., Carriage Return, Line Feed, Form Feed). If
the delay is not adequate you will have to reset it. The delays are given
in the range of $00 to $FF characters which specify the number of characters
that would be sent during the delay specified. After the CR, LF, or FF the
RS 232 driver will wait for the time it would take to transmit the amount of
characters specified before it sends the following character.
DCB 02 = Delay After Carriage Return
DCB 03 = Delay After Line Feed
DCB 04 = Delay After Form Feed
DCB $05 thru $0B = FLOW CONTROL
For protocol - Set $05 $06 $07 $08 $09 $0A $0B DCBs to:
none - $00 $00
XON/XOFF - $80 $13 $11 $DF $84 $00
ENQ/ACK - $40 $05 $06 $50
ETX/ACK - $40 $03 $06 $50
DTR HW Hndshk- $00 $DF $84 $80