By:
Masud-ul-Hasan
4
TMOD
: Counter/Timer MODe Register
GATE C/T M1 M0 GATE C/T M1 M0
Timer 1 Timer 0
- C/T : Set for counter operation, reset for timer operation.
- M1, M0 : To Select the Mode
00 : Mode 0 - 13-bit timer mode (Emulates
8048).
01 : Mode 1 - 16-bit timer mode.
10 : Mode 2 - 8-bit auto-reload mode.
11 : Mode 3 - Split timer mode (Timer 0 = two
8-bit timers).
• TMOD is not bit addressable. It is loaded, generally, by the software at the beginning of a program to
initialize the timer mode.
- GATE : Permits INTx pin to enable/disable the counter.
