Programming And Initialization; Introduction; Input Programming - ZiLOG Z80-AIO Hardware User Manual

SECTION 4: PROGRAMMING AND INITIALISATION
4.1
The following section contains Information and programming
examples for analog input/output Operation.

4.2 Input Programming

The first four locations (80H-83H), are used to program the
onboard PIO. A detailed description of the PIO's Operation
can be found in the Zilog Z80-PIO Product Specification.
Normal Operation of the board reauires programming the PIO äs
Polling Mode - Both A and B Mode Control registers must be
set for input (mode 1) .
analog to digital Converter can be input to the processor.
In addition, the Interrupt Enable must be turned off.
following initialization program illustrates the procedure.
DI
LD A, 4FH
OUT 82H, A
OUT 83H, A
LD A, 07H
OUT 82H, A
OUT 83H, A
IN A, 80H
IN A, 81H
The remaining board locations are treated äs described in the
following paragraph discussing non-PIO locations.
When Mode l is active, data from the
DISABLE INTERRUPT
; SET PORT A FOR MODE l
SET PORT B FOR MODE l
; DISABLE PORT A INTERRUPT
; DISABLE PORT B INTERRUPT
INITIALIZE CONVERSION READ F.F,
INITIALIZE CONVERSION READ F.F,
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The