W77C32_07 Datasheet, PDF (55/78 Pages) Winbond – 8-BIT MICROCONTROLLER

W77C32/W77C032A
Clock Source
Mode input
div. by 4 osc/1
div. by 64 osc/16
div. by 1024 osc/256
T2 = P1.0
TR2 = T2CON.2
T2EX = P1.1
T2M = CKCON.5
1/4
1 _{C/T2 = T2CON.1}
0
1/12 0
1
EXEN2 = T2CON.3
TL2 TH2
T2CON.7
TF2
RCAP2L RCAP2H
L
EXF2
T2CON.6
Timer 2
Interrupt
Figure 15. 16-Bit Auto-reload Mode, Counting Up
12.2.3 Auto-reload Mode, Counting Up/Down
Timer/Counter 2 will be in auto-reload mode as an up/down counter if CP/ RL2 bit in T2CON is
cleared and the DCEN bit in T2MOD is set. In this mode, Timer/Counter 2 is an up/down counter
whose direction is controlled by the T2EX pin. A 1 on this pin cause the counter to count up. An
overflow while counting up will cause the counter to be reloaded with the contents of the capture
registers. The next down count following the case where the contents of Timer/Counter equal the
capture registers will load an FFFFh into Timer/Counter 2. In either event a reload will set the TF2 bit.
A reload will also toggle the EXF2 bit. However, the EXF2 bit can not generate an interrupt while in
this mode.
Clock Source
Mode input
div. by 4 osc/1
div. by 64 osc/16
div. by 1024 osc/256
1/4
1/12
T2 = P1.0
TR2 = T2CON.2
T2M = CKCON.5
1 ^{C/T = T2CON.1}
0
0
1
Down Counting Reload Value
0FFh 0FFh
TL2 TH2
T2EX = P1.1
RCAP2L RCAP2H
Up Counting Reload
Vl
DCEN = 1
Figure 16. 16-Bit Auto-reload Up/Down Counter
T2CON.7
Timer 2
TF2
Interrupt
EXF2
T2CON.6
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Publication Release Date: February 1, 2007
Revision A8