W78E054D Datasheet, PDF (52/89 Pages) List of Unclassifed Manufacturers – 8-bit microcontroller

W78E054D/W78E052D Data Sheet
Fosc
T2=P1.0
TR2=T2CON.2
1/12
C/T2=T2CON.1
0
1
TL2 TH2
T2CON.7
TF2
RCAP2L RCAP2H
Timer2
Interrupt
T2EX=P1.1
EXEN2=T2CON.3
EXF2
T2CON.6
Figure 14–4 16-Bit Capture Mode
14.3.2 Auto-Reload Mode, Counting up
The auto-reload mode as an up counter is enabled by clearing the ^{CP / RL2} bit in the T2CON register
and clearing the DCEN bit in T2MOD(bit0) register. In this mode, Timer/Counter 2 is a 16 bit up coun-
ter. When the counter rolls over from 0FFFFh, a reload is generated that causes the contents of the
RCAP2L and RCAP2H registers to be reloaded into the TL2 and TH2 registers. The reload action also
sets the TF2 bit. If the EXEN2 bit is set, then a negative transition of T2EX pin will also cause a reload.
This action also sets the EXF2 bit in T2CON.
Fosc
T2=P1.0
TR2=T2CON.2
(RCLK,TCLK, CP/RL2 )= (0,0,0) & DCEN= 0
1/12
C/T2=T2CON.1
0
1
TL2 TH2
T2CON.7
TF2
Timer2
Interrupt
RCAP2L RCAP2H
EXF2
T2CON.6
Figure 14–5 16-Bit Auto-reload Mode, Counting Up
14.3.3 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 over-
flow 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 regis-
ters will load a 0FFFFh 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 cannot generate an interrupt while in this mode.
(RCLK,TCLK, CP/RL2 )= (0,0,0) & DCEN= 1
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Publication Release Date: Jun 9, 2015
Revision A13