DS80C390_00 Datasheet, PDF (16/155 Pages) Dallas Semiconductor – High-Speed Microcontroller User’s Guide Supplement

DS80C390 High-Speed Microcontroller User’s Guide Supplement
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
C/ T
Bit 6
M1, M0
Bits 5-4
GATE
Bit 3
C/ T
Bit 2
M1, M0
Bits 1-0
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.
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
00
Mode 0: 8 bits with 5-bit prescale
01
Mode 1: 16 bits
10
Mode 2: 8 bits with auto-reload
11
Mode 3: Timer 1 is halted, but holds its count
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.
Timer 0 Counter/Timer Select.
0 = Timer incremented by internal clocks.
1 = Timer 1 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.
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