Apple IIc Printer/Modem port - 5 Pin
DIN female connector
| Pin | Signal | Name | Notes |
|---|---|---|---|
| 1 | DTR | Data Terminal Ready | becomes active when the IIc is ready to go on line |
| 2 | TD | Transmit Data | conveys serial data sent from the IIc |
| 3 | SG | Signal Ground | is used to provide a common ground reference for the electronics in both the IIc and the device it is connected to |
| 4 | RD | Receive Data | receives serial data sent from the device to the IIc it is connected to |
| 5 | DSR | Data Set Ready | is asserted by the device the IIc is connected to when it is ready to go on line |
Notes
- The serial ports on an Apple IIc are essentially identical, the pin connections being the same on both. The main difference being that the printer port is pre-configured for 9600 baud and the communication port is preconfigured for 300 baud. The printer port appears to the software as slot 1, the communication port as slot 2. The settings of these ports can be changed with the Apple IIc System Utilities disk. Please see the System Utilities manual for precise details.
CHARACTERISTICS AT STARTUP
The Apple IIc’s ports are configured with keyboard commands instead of DIP switches. After power-up, the IIc sets the printer port to the default configuration given below:
- 9600 baud
- 8 data bits and no parity
- 2 stop bits
- 80 chars per line
- LF after CR
- Command character is CTRL-I
- Hardware (DTR flow control protocol) handshake.