SONIX SN8P2624 - 8.2.3 TOC Counting Register

SN8P2624
8-Bit Micro-Controller
SONiX TECHNOLOGY CO., LTD Page 74 Version 0.3
8.2.3 T0C COUNTING REGISTER
T0C is an 8-bit counter register for T0 interval time control.
0D9H Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
T0C
T0C7 T0C6 T0C5 T0C4 T0C3 T0C2 T0C1 T0C0
Read/Write R/W R/W R/W R/W R/W R/W R/W R/W
After reset 0 0 0 0 0 0 0 0
The equation of T0C initial value is as following.
T0C initial value = 256 - (T0 interrupt interval time * input clock)
¾ Example: To set 10ms interval time for T0 interrupt. High clock is external 4MHz. Fcpu=Fosc/4. Select
T0RATE=010 (Fcpu/64).
T0C initial value = 256 - (T0 interrupt interval time * input clock)
= 256 - (10ms * 4MHz / 4 / 64)
= 256 - (10
-2
* 4 * 10
6
/ 4 / 64)
= 100
= 64H
The basic timer table interval time of T0.
High speed mode (Fcpu = 4MHz / 4) Low speed mode (Fcpu = 32768Hz / 4)
T0RATE T0CLOCK
Max overflow interval One step = max/256 Max overflow interval One step = max/256
000 Fcpu/256 65.536 ms 256 us 8000 ms 31250 us
001 Fcpu/128 32.768 ms 128 us 4000 ms 15625 us
010 Fcpu/64 16.384 ms 64 us 2000 ms 7812.5 us
011 Fcpu/32 8.192 ms 32 us 1000 ms 3906.25 us
100 Fcpu/16 4.096 ms 16 us 500 ms 1953.125 us
101 Fcpu/8 2.048 ms 8 us 250 ms 976.563 us
110 Fcpu/4 1.024 ms 4 us 125 ms 488.281 us
111 Fcpu/2 0.512 ms 2 us 62.5 ms 244.141 us