Maxim Integrated High-Speed Microcontroller - Manual (Page 29)

High-Speed Microcontroller User’s Guide
Rev: 062210 29 of 176
4.2.10 Timer Mode Control (TMOD)
7 6 5 4 3 2 1 0
SFR 89h GATE C/ T M1 M0 GATE C/ T M1 M0
RW-0 RW-0 RW-0 RW-0 RW-0 RW-0 RW-0 RW-0
R = Unrestricted Read, W = Unrestricted Write, -n = Value after Reset
GATE
Bit 7 Timer 1 Gate Control. This bit enable/disables the ability of Timer 1 to increment.
0 = Timer 1 will clock when TR1 = 1, regardless of the state of
INT1.
1 = Timer 1 will clock only when TR1 = 1 and INT1 = 1.
C/ T
Bit 6
Timer 1 Counter/Timer Select.
0 = Timer 1 is incremented by internal clocks.
1 = Timer 1 is incremented by pulses on T1 when TR1 (
TCON .6) is 1.
Timer 1 Mode Select. These bits select the operating mode of Timer 1.
M1 M0 Mode
0 0 Mode 0: 8 bits with 5-bit prescale
0 1 Mode 1: 16 bits
1 0 Mode 2: 8 bits with auto-reload
1 1 Mode 3: Timer 1 is halted, but holds its count
M1, M0
Bits 5, 4
GATE
Bit 3 Timer 0 Gate Control. This bit enables/disables that ability of Timer 0 to increment.
0 = Timer 0 will clock when TR0 = 1, regardless of the state of
INT0.
1 = Timer 0 will clock only when TR0 = 1 and INT0 = 1.
C/
T
Bit 2
Timer 0 Counter/Timer Select.
0 = Timer 0 incremented by internal clocks.
1 = Timer 0 is incremented by pulses on T0 when TR0 (
TCON .4) is 1.
Timer 0 Mode Select. These bits select the operating mode of Timer 0. When Timer 0
is in mode 3, TL0 is started/stopped by TR0 and TH0 is started/stopped by TR1. Run
control from Timer 1 is then provided via the Timer 1 mode selection.
M1 M0 Mode
0 0 Mode 0: 8 bits with 5-bit prescale
0 1 Mode 1: 16 bits
1 0 Mode 2: 8 bits with auto-reload
1 1 Mode 3: Timer 0 is two 8-bit counters.
M1, M0
Bits 1, 0