Pepper Computer RS485, RS232 user manual Example for a Square Wave Generator

SMART I/O User’s Manual Chapter 2 SMART-BASE

Example for a Square Wave Generator

The Timer Control Register

7	6	5	4	3	2	1	0
			Z.D.		Clock		Timer
	TOUT/TIAC			•
	Control		Control		Control		Enable
0	1	x	0	0	00 or 1x		Changed

In this configuration, the timer produces a square wave at the TOUT pin which is connected to the user’s circuitry. The TIN pin may be used as a clock input. The processor loads the counter preload registers and the timer control register and then enables the timer. When the 24-bit counter passes from $000001 to $000000, the ZDS status bit is set and the TOUT is toggled. At the next clock to the 24-bit counter it is again loaded with the contents of the CPRs and thereafter decrements.

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