The SC118, Z80 Processor Card can be used in two basic ways:

• As a Single Board Computer (SBC).

• As the processor card in a Z50Bus system.

Single Board Computer

This card can be used in a modest say as a Single Board Computer. The card is connected to a computer or terminal with an FTDI style serial adapter. This also provides the 5V 100mA power for the card.

This serial port is very basic, providing only a software generated 9600 baud, 8 data bit, 1 stop bit, no parity serial interface. It is designed to provide a very low cost ‘starter’ port to get the system up and running as easily and cheaply as possible. It is suitable for simple applications, but a more capable serial module should be added for sophisticated applications such as running CP/M.

The pin-out, below, describes signals with respect to the card, so an output is and signal from the card to a computer or terminal.

Pin	Function
1	Ground (GND)
2	Request To Send (RTS) output
3	Vcc (5V)
4	Recieve Data (RxD) input
5	Transmit Data (TxD) output
6	Clear To Send (CTS) input (not connected)

Z50Bus System

A more capable system can be created using this card as the processor and memory for a Z50Bus computer.

The most likely first addition would be an SC125, Serial card. This provides two asynchronous serial ports, software controlled baud rates, and a timer.