Force Computers SYS68K/CPU-40, User Manual

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SYS68K/CPU-40/41 USER'S MANUAL FORCE COMPUTERS
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Table 3-10: Ports #3 and #4 (DUSCC2) Common Registers Address Map
Port Base Address : $FF802200
Address Offset Reset Mode Label Description
HEX HEX Value
$FF80221B 1B 00 R/W DUSCMR1 Channel Mode Reg 1
$FF80221E 1E 0F R/W DUSCMR2 Channel Mode Reg 2
$FF80221F 1F 00 R/W DUSSS1R SYN1/Secondary Adr Reg 1
$FF80223E 3E 0F R DUSS2R SYN2/Secondary Adr Reg 2
3.8.8 RS232 Hardware Configuration of Ports #3 and #4
Ports #3 and #4 are built around the DUSCC (J24). DUSCC2 is connected to the local 8 bit data bus and
is accessible in the byte mode. The RS232 interfaces of port #3 and #4 which are wired to the two 9-pin
Micro D-Sub connectors (named "3" and "4") on the front panel are identical. All RS232 driver and receivers
are installed in the default configuration. The individual I/O signal assignment of the two channels is listed
as follows:
Signal Input Output 9 Pin D-Sub Connector Description
DCD X 1 Data Carrier Detect
RXD X 2 Receive Data
TXD X 3 Transmit Data
DTR X 4 Data Terminal Ready
GND 5 Signal GND
DSR X X 6 Data Set Ready
RTS X 7 Request to Send
CTS X 8 Clear to Send
GND 9 Signal GND
The following figure displays the connection between DUSCC2 and the D-Sub connectors.