Specifications

Table Of Contents

SkyePlus™ MXH and MXU Multiplexer Reference Guide

Appendix A

Using the SkyePlus Multiplexer with Other

Devices

Code for Third-Party Readers

The following code examples show how a typical microcontroller can control the

SkyePlus multiplexer through general purpose I/O ports. The examples are in

the C programming language.

These code examples show a general implementation but

are therefore not

optimized for any single platform. Using one I/O port and performing read and

write functions with a single mask can simplify the bit manipulations and reduce

computation cycles. To use the sample code, specify the I/O port, direction

registers, and appropriate bit masks in the header file.

The SkyePlus multiplexer uses 20k

pull-up and pull-down resistors on the

control lines for device detection. When i

nterfacing the SkyePlus multiplexer to

other devices, the devices must be capable of driving these control lines. When

detecting the SkyePlus multiplexer, you may need to disable any internal pull-

ups or pull-downs in the device.