Omega 1002 manual Timer, A/D trigger

4.2 The 8254 Timer

The OME-PCI-1002 series provide 3 independent 16-bit timer/counters. Each timer has a different function. Timer 0 is used as

Pacer 0. Timer 1 is used as Pacer 1. Timer 2 is used as the machine

independent timer. The block diagram is given as follows:

		VCC		4 M Hz
		EN	CLK
		Timer 0		Pacer 0
			OUT1
Local Data Bus			CLK
D0…D7
		Timer 1		Pacer 1
User
		EN	OUT2
			CLK	Status
		Timer
	8254	EN	OUT3
Figure 4-2. 8254 Block Diagram.

4.3 The A/D trigger

The block diagram of the A/D trigger is shown below:

			8254
		Timer 0
		Software Trigger			Mux	To A/D
0		PR	External Trigger
	D
1		Q	EN	8254
External		RS	CLK	Timer 1	Select
Trigger.
			4M-Hz		Trigger Select
Figure 4-3. A/D Trigger Controller.

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