IOX Data Sheet

Version 1.0

Comm link to Host

LCD Display

Frequency Counter

Keypad

A/D Converter

Digital Potentiometer

IOX System

 

TABLE 1: I/O Expander Command-Response Structure

COMMAND

FUNCTION

RESPONSE

LCD:

 

 

1

Clear entire display

 

2

Clear 1st line & home cursor

 

3

Clear 2nd line & home cursor

 

8

Blank LCD (retains data)

 

12

Hide cursor

 

14

Show cursor

 

128+n

Position cursor at the nth character of 1st line

 

192+n

Position cursor at the nth character of 2nd line

 

FREQ COUNTER:

 

 

65

Measure Frequency

 

66

Readout Counting Registers

3 Bytes ($00-$FF)

67

Readout Frequency String

6 BCD Byte (range: each $0-$9)

68

Set 1:1 Pre-scale

 

69

Set 1:4 Pre-scale

 

A/D:

 

 

80

Read A/D

Byte ($00-$FF)

DIGITAL POT:

 

 

90, n

Set wiper to n (0-to-99)

 

91,n

Increment wiper n steps

 

92,n

Decrement wiper n steps

 

KEYPAD:

 

 

100

Read Keypad

Byte ($00-$0B)

101

Wait Keypad

Byte ($00-$0B)

SYSTEM:

 

 

200

Reset IOX software

ACK

 

Last Modified:  November 15, 2002