This example demonstrates one way to connect an alphanumeric LCD to a parallel port. The example code has been written as a Small Computer Monitor App.

Typically, the display will have 2 lines with 16 characters in each line.

The display is connected to either a simple digital output
port (such as SC129) or to a Z80 PIO (such as SC103).

This interfacing method uses 4-bit data mode and uses time delays rather than polling the display’s ready status. As a result the interface only requires 6 simple output lines, as shown below.

Source code can be found here.

The example source code supports a number of hardware combinations selected by a #DEFINE statement. These are the I/O addresses used by the different #DEFINE builds:

Build	Device	Address
LINC80	LiNC80 SBC1 Z80 PIO	0x18
RC2014	RC2014 plus SC104 Z80 PIO	0x68
Z280RC	Z280RC SBC plus SC104 Z80 PIO	0x68
SC129	SC129 digital I/O	0x0D

WARNING: Some of the pictures below show the hardware configured to I/O addresses other than the defaults in the example code.

Here are some of the hardware combinations supported by the example code:

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