Chapter 1
Introducing the CIO-DIO48H
Overview: CIO-DIO48H features
The CIO-DIO48H provides 48-bits of digital I/O. The I/O is organized into two 24-bit groups based on an 82C55 mode 0 emulation. Each 24-bit group is divided into three eight-bit ports labeled An, Bn and Cn, where n is either "1" for FIRSTPORT or "2" for SECONDPORT. Port C can be split into two four-bit nibbles — Port C-HI and Port C-LO. Each of these ports may be individually programmed as input or output.
All digital inputs are LSTTL. The output signals are buffered high output drive TTL. The digital output drivers are 74S244 chips that can sink 64 mA and source 15 mA. The input buffers are 74LS373 chips and have standard high input impedance of the 74LS series devices.
On power up and reset, all I/O bits are set to input mode. If you are using the board to control items that must be OFF on reset, install pull-down resistors. The board is equipped with open locations where you can install SIP resistor networks for either pull-up or pull-down.
All signals pass through a 50-pin connector.
Software features
For information on the features of InstaCal and the other software included with your CIO-DIO48H, refer to the Quick Start Guide that shipped with your device. The Quick Start Guide is also available in PDF at www.mccdaq.com/PDFmanuals/DAQ-Software-Quick-Start.pdf.
Check www.mccdaq.com/download.htm for the latest software version.
7
