Diamond Systems Comprehensive Guide to p11-pc104 External Trigger Register and Digital I/O for Ruby-MM-1612

 Page 11

Base + 3, Write: External trigger register

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Bit No.

7

 

6

5

4

3

2

1

0

 

 

 

 

 

 

 

 

 

 

 

 

Name

X

 

X

X

X

X

X

X

TRIGEN

 

 

 

 

 

 

 

 

 

 

 

X

Bit not used. These bits will be ignored.

 

 

 

 

 

TRIGEN

External trigger enable. 1 = enable, 0 = disable. When external trigger is enabled, digital

 

I/O line C0 will update all DACs simultaneously when it is brought low. This can be done

 

either by an external signal, when C0 is in input mode, or in software, when C0 is in

 

output mode.

 

 

 

 

 

 

 

 

If using an external trigger, make sure that the lower half of Port C is in input mode.

Base + 4 through Base + 7

Read/Write

82C55 Digital I/O Registers

These registers map directly to the 82C55 digital I/O chip. The definitions of these registers can be found in the 82C55 datasheet appended to the back of this manual. A short form description is on the next page.

These lines power up in input mode. Each line has a 10KΩ pull-up resistor, so on power-up or system reset, all lines will indicate a logic high.

Copyright 2001 Diamond Systems Corp.

Ruby-MM-1612 User Manual V1.1 P. 11

Page 10 Page 12
Image 11
Page 10 Page 12
Contents
RUBY-MM-1612 Table of Contents Description O Header Pinout Signal Name DefinitionBase Address Board ConfigurationBase Address Configuration Header J5 Position Hex Decimal Full-Scale Voltage Analog Output Range ConfigurationAdjustable Reference Voltage On-Board Reference Full-Scale Voltage SelectionAnalog Output Configuration Header J4 Range RUBY-MM-1612 Board Drawing Base + Write Function Read Function Reset informationRuby-MM-1612 I/O Map Base + 1, Write DAC MSB register Base + 0 or 1, Read Update DACsRegister Definitions Base + 0, Write DAC LSB registerBase + 3, Write External trigger register Definitions Configuration Register82C55 Digital I/O Chip Operation 82C55 Register MapFull Scale Analog Output Ranges and ResolutionFull Scale 1LSB 10. D/A Code Computation Output Code Explanation Output Voltage for ±5V Range Offset Binary Coding for bipolar output rangesLSB = 1/2048 x Full-Scale Voltage To generate an analog output on one or more channels HOW to Generate AN Analog OutputHardware Update Command Two channel output Examples Single channel outputCalibration Procedure Miscellaneous SpecificationsPinouts FeaturesOrdering Information Description82C55A Pin Description Functional DiagramGroup a and Group B Controls 82C55A Functional DescriptionData Bus Buffer Read/Write and Control LogicPorts A, B, and C Mode Selection82C55A Operational DescriptionInte Flip-Flop Definition Single Bit Set/Reset Feature FigureOperating Modes Interrupt Control FunctionsMode 0 Configurations Mode 0 Basic InputMode 0 Basic Output Control Word #4 Control Word #8 IBF Input Buffer Full F/F Input Control Signal DefinitionSTB Strobe Input Intr Interrupt Request Output Control Signal DefinitionInput Operations Mode 2 Strobed Bi-Directional Bus I/OBi-Directional Bus I/O Control Signal Definition Output OperationsMode Control Word Mode 2 Combinations Current Drive Capability Special Mode Combination ConsiderationsReading Port C Status Figures 15 Applications of the 82C55A