User's Manual

Troubleshooting and Diagnostics

Chapter

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116

6820 Series 80-Column Printer User’s Manual

The printer has a 25-pin connector with the following pinout designations

and signal mnemonics:

Printer Communications Connector Pin-Outs

15-Pin

D-Sub

25-Pin

D-Sub

Signal Name Type I/O Description

1 NC NC – – – – – – NC (No Connection)

2 20 NC ––– ––– NC

3 4 CTS (Clear To Send) RS-232 IN Wake up

4 2 RXD (Receive Data) RS-232 IN Printer’s RxD

5 3 TXD (Transmit Data) RS-232 OUT Printer’s TxD

6 5 RTS (Ready To Send) RS-232 OUT IrDA baud rate select

7 6 DTR (Data Terminal Ready) RS-232 OUT IrDA baud rate select

8 9 HHC_CHARGE POWER OUT 7.5–15 V, up to 1 A per contact

9 7 GND POWER SG (Signal Ground)

10 NC NC ––– –––

11 11 IO_SENSE 0–5 V

ANALOG

IN Analog input signal for I/O board type

detection. Normally tied to +5 V.

NC 12 DOCK_A/B_SW ––– IN Bluetooth Adapter configuration signal

12 18 IOB_RESET TTL OUT Signal to hold I/O board in reset.

13 25 TTL_POWER POWER OUT Power for I/O board logic (never shuts off)

14 NC NC ––– –––

NC NC NC ––– IN Switched 5 V from computer.

NC NC V_IN ––– ––– Unswitched input power from printer.