Measurement Specialties Functional Description, PCI-DAS64/M2/16 block diagram, Analog inputs

Chapter 4

Functional Description

PCI-DAS64/M2/16 block diagram

The PCI-DAS64/M2/16 is a multifunction measurement and control board that provides the following features:

!32 differential or 64 single-ended 16-bit analog inputs

!Two 16-bit analog outputs

!32 digital I/O channels

!One 16-bit counter

PCI-DAS64/M2/16 functions are illustrated in the block diagram shown here.

Queue

ADC

DAC 0/1

32K x 16

Gain and Offset Autocal

Buffer

Buffer

Buffer

Gain and Offset Autocal

Holding

(8K)

(8K)

(16K)

SRAM

D/A OUT0

REG

DAC0

Mux

16-bit, 100 kHz

Analog In

&

16-bit

Memory Bus

64-CH single-ended

ADC

D/A OUT1

Gain

EOC

DAC1

32-CH differential

2 MHz

16-bit, 100 kHz

16

TRIG_LO TRIG_HI

Analog

Trigger

A/D Start/Stop Trigger

A/D Pacer Gate

A/D External Pacer

SSH Out
A/D Internal Pacer Out
	24-bits DIO
FIRSTPORTA (7:0)	PortA	Control
FIRSTPORTB (7:0)	PortB

FIRSTPORTC (7:0) PortC

DIN (3:0) Inputs

DOUT (3:0) Outputs

		STC
	ADC	Memory	DAC	External D/A Trigger/Pacer Gate
	CNTL
		CNTL	CNTL	D/A External Pacer In
	Trigger
	CNTL		DAC	DAC Pacer Out
	ADC	Queue	Pacer
	Pacer	CNTL	DAC RT
	Sample
			CNTL
	CNTL
	Control /	Decoder	DMA IRQ	Interrupt In
40 MHz	Status		CTRLCTRL
	Regs

					Control	0
							User
				Local Bus		CNTR
		16
	PCI Bridge		DMA					CTR1 GATE
Boot			CH0
EEPROM	w/BUS Master		DMA					CTR1 CLK
			CH1					CTR1 OUT

PCI Bus (5V, 32-bit, 33 MHz)

Figure 4-1. PCI-DAS64/M2/16 functional bock diagram

Analog inputs

The PCI-DAS64/M2/16 provides 32 fully differential or 64 single-ended analog inputs. The input mode is software selectable, with no switches or jumpers to set. The PCI-DAS64/M2/16 offers a 2 MHz sample rate. The board offers full speed acquisition in single channel scans, and will perform full accuracy multi-channel scans of up to 1.5 MHz, depending on the operating mode. An 8 K sample gain/channel queue is available making long, complex sample sequencing simple. An 8 K sample FIFO buffer combines with Bus-Master DMA and scatter-gather to assure data taken from the board is transferred into computer memory without missing samples.

4-1