DS89C420-QCL Datasheet, PDF (20/139 Pages) Maxim Integrated Products – Ultra-High-Speed Flash Microcontroller User’s Guide

Ultra-High-Speed Flash
Microcontroller User’s Guide
Timer Mode Control (TMOD)
7
6
5
SFR 89h
GATE
C/T
M1
RW-0
RW-0
RW-0
R = Unrestricted read, W = Unrestricted write, -n = Value after reset
4
M0
RW-0
3
GATE
RW-0
2
C/T
RW-0
1
M1
RW-0
0
M0
RW-0
GATE
Bit 7
C/T
Bit 6
M1, M0
Bits 5, 4
Timer 1 Gate Control. This bit enables/disables the ability of Timer 1 to increment.
0 = Timer 1 clocks when TR1 = 1, regardless of the state of INT.
1 = Timer 1 clocks 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.
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 autoreload
1 1 Mode 3: Timer 1 is halted, but holds its count
GATE
Bit 3
C/T
Bit 2
M1, M0
Bits 1, 0
Timer 0 Gate Control. This bit enables/disables the ability of Timer 0 to increment.
0 = Timer 0 clocks when TR0 = 1, regardless of the state of INT0.
1 = Timer 0 clocks 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 by the Timer 1 mode selection.
Timer 0 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 autoreload
1 1 Mode 3: Timer 0 is two 8-bit counters
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