9.2.4Timer Count Registers

(T0CNT, Offset 50h, T1CNT, Offset 58h, T2CNT, Offset 60h)

These registers can be incremented by one every four internal processor clocks. Timer 0 and timer 1 can also be configured to increment based on the TMRIN0 and TMRIN1 external signals, or they can be prescaled by timer 2. See Figure 9-3.

The count registers are compared to maximum count registers and various actions are triggered based on reaching a maximum count.

Figure 9-3 Timer Count Registers (T0CNT, T1CNT, T2CNT, offsets 50h, 58h, and 60h)

15

7

0

TC15–TC0

The value of these registers at reset is undefined.

Bits 15–0: Timer Count Value (TC15–TC0)—This register contains the current count of the associated timer. The count is incremented every fourth processor clock in internal clocked mode, or each time the timer 2 maxcount is reached if prescaled by timer 2. Timer 0 and timer 1 can be configured for external clocking based on the TMRIN0 and TMRIN1 signals.

9-6

Timer Control Unit

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AMD Am186TMER, Am188TMER user manual TC15-TC0