Functional Description; Introduction; Basic Architecture; Auxiliary Input & Output Interface - Measurement Computing PCI-DAS6034 User Manual

PCI-DAS6034 & PCI-DAS6035 User's Guide
4.1

Introduction

Figure 4-1 is a simplified block diagram of the PCI-DAS6035 and PCI-DAS6034. The PCI-
DAS6035 provides all the functional elements shown in the figure. The PCI-DAS6034 does
not provide D/A outputs.
Except for this difference, the two boards are identical in all other respects.

4.1.1 Basic Architecture

The STC (System Timing and Control) is the logical center for all DAQ, DIO, and DAC (if
applicable) operations. It communicates over two major busses: a Local bus and a Memory
bus.
The Local bus carries digital I/O data and software commands from the PCI Bus Master.
There are two Direct Memory Access (DMA) channels provided for data transfers to the PC.
Primarily, the memory bus carries A/D and D/A (PCI-DAS6035 only) related data and
commands. There are three buffer memories provided on the memory bus:
• Use the Queue Buffer (8K configuration memory) to store programmed channel
numbers, gains, and offsets.
• Use the ADC Buffer (8K FIFO [First In, First Out]) to temporarily store scanned and
converted analog inputs.
• Use the DAC 16K Buffer to store data to be output as analog waveforms (this buffer
function only applies to the PCI-DAS6035).
4.1.2 Auxiliary Input & Output Interface
The board's 100-pin I/O connector provides six software-selectable inputs, and three
software-selectable outputs. The signals are user-configurable clocks, triggers and gates.
Refer to section 4-2 for additional descriptions and timing requirements for the signals.
Table 4-2 lists all the possible and the default signals that can be used on the nine pins. Note
that the D/A signals pertain only to the PCI-DAS6035.

4 Functional Description

4–1
Functional Description