SAB80C515A-M18-T3 Siemens Semiconductor Group, SAB80C515A-M18-T3 Datasheet - Page 28

• Manufacturer Part Number: SAB80C515A-M18-T3
• Description: 8-Bit CMOS Single-Chip Microcontroller
• Manufacturer: Siemens Semiconductor Group

Timers /Counters
The SAB 80C515A contains three 16-bit timers/counters wich are useful in many applications
for timing and counting. the input clock for wach timer/counter is 1/12 of the oscillator frequency
in the timer operation or can be taken from an external clock source for the counter operation
(maximum count rate is 1/24 of the oscillator frequency).
– Timer/Counter 0 and 1
These timers/counters can operate in four modes:
Mode 0:
Mode 1:
Mode 2:
Mode 3:
External inputs INTO and INT1 can be programmed to function as a gate for timer/counters 0
and 1 to facilitate pulse width measurements.
– Timer/Counter 2
Timer/counter 2 of the SAB 80C515A is a 16-bit timer/counter with several additional features.
It offers a 2:1 prescaler, a selectable gate function, and compare, capture and reload functions.
Corresponding to the 16-bit timer register there are four 16-bit capture/compare registers, one
of them can be used to perform a 16-bit reload on a timer overflow or external event. Each of
these registers corresponds to a pin of port 1 for capture input/compare output.
Figure 4 shows a block diagram of timer/counter 2.
Reload
A 16-bit reload can be performed with the 16-bit CRC register consisting of CRCL and CRCH.
There are two modes from which to select:
Mode 0:
Mode 1:
Semiconductor Group
8-bit timer/counter with 32:1 prescaler
16-bit timer/counter
8-bit timer/counter with 8-bit auto-reload
Timer/counter 0 is configured as one 8-bit timer/counter and one
8-bit timer; Timer/counter 1 in this mode holds its count.
Reload is caused by a timer 2 overflow (auto-reload).
Reload is caused in response to a negative transition at pin T2EX
(P1.5), which can also request an interrupt.
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SAB 80C515A/83C515A-5