Timers
16-Bit Timer Setup Examples
MN102H75K/F75K/85K/F85K LSI User Manual Panasonic Semiconductor Development Company
103
Panasonic
To set up timer 4:
Use the MOV instruction for this
setup and only use 16-bit write
operations.
This step stops the TM4BC
count and clears both TM4BC
and the S-R flip-flop to 0.
1. Set the operating mode in the timer 4 mode register (TM4MD). Disable
timer 4 counting and interrupts. Select up counting. Select timer 0 under-
flows as the clock source.
TM4MD (example) x’00FE80’
2. Set the divide-by ratio for timer 4. To divide timer 0 underflow by 5, write
x’0004’ to timer 4 compare/capture register A (TM4CA). (The valid range
for TM4CA is x’0001’ to x’FFFE’.)
TM4CA (example) x’00FE84
3. Set the phase difference for timer 4. For a phase difference of two timer 0
underflow cycles, write x’0001’ to timer 4 compare/capture register B
(TM4CB). (The valid range is -1 < TM4CB < the TM4CA value.)
TM4CB (example) x’00FE88
4. Write a dummy data word (of any value) to TM4CAX. In double-buffer
mode, TM4CA is compared to TM4CAX. The contents of TM4CA are
loaded to TM4CAX when TM4BC = TM4CAX. However, since TM4CAX
is undefined or x’0000’ before this operation starts, this initial dummy write
prevents timing errors.
5. Write a dummy data word (of any value) to TM4CBX. In double-buffer
mode, TM4CB is compared to TM4CBX. The contents of TM4CB are
loaded to TM4CBX when TM4BC = TM4CBX. However, since TM4CBX
is undefined or x’0000’ before this operation starts, this initial dummy write
prevents timing errors.
Bit:1514131211109876543210
TM4
EN TM4
NLD ——
TM4
UD1 TM4
UD0 TM4
TGE TM4
ONE TM4
MD1 TM4
MD0 TM4
ECLR TM4
LP TM4
ASEL TM4
S2 TM4
S1 TM4
S0
Setting:0000000001011000
Bit:1514131211109876543210
TM4
CA15 TM4
CA14 TM4
CA13 TM4
CA12 TM4
CA11 TM4
CA10 TM4
CA9 TM4
CA8 TM4
CA7 TM4
CA6 TM4
CA5 TM4
CA4 TM4
CA3 TM4
CA2 TM4
CA1 TM4
CA0
Setting:0000000000000100
Bit:1514131211109876543210
TM4
CB15 TM4
CB14 TM4
CB13 TM4
CB12 TM4
CB11 TM4
CB10 TM4
CB9 TM4
CB8 TM4
CB7 TM4
CB6 TM4
CB5 TM4
CB4 TM4
CB3 TM4
CB2 TM4
CB1 TM4
CB0
Setting:0000000000000001