
Philips Semiconductors
Product data
P87C51RA2/RB2/RC2/RD2
80C51 8-bit microcontroller family 8KB/16KB/32KB/64KB OTP
with 512B/1KB RAM, low voltage (2.7 to 5.5 V), low power, high
speed (30/33 MHz)
2003 Jan 24
18
OSC
÷ n*
C/T2 = 0
C/T2 = 1
TR2
CONTROL
TL2
(8 BITS)
TH2
(8 BITS)
TF2
RCAP2L
RCAP2H
EXEN2
CONTROL
EXF2
TIMER 2
INTERRUPT
T2EX PIN
TRANSITION
DETECTOR
T2 PIN
RELOAD
SU01253
* n = 6 in 6-clock mode, or 12 in 12-clock mode.
Figure 4. Timer 2 in Auto-Reload Mode (DCEN = 0)
÷ n*
C/T2 = 0
C/T2 = 1
TL2
TH2
TR2
CONTROL
T2 PIN
SU01254
FFH
RCAP2L
RCAP2H
(UP COUNTING RELOAD VALUE)
T2EX PIN
TF2
INTERRUPT
COUNT
DIRECTION
1 = UP
0 = DOWN
EXF2
OVERFLOW
(DOWN COUNTING RELOAD VALUE)
TOGGLE
OSC
* n = 6 in 6-clock mode, or 12 in 12-clock mode.
Figure 5. Timer 2 Auto Reload Mode (DCEN = 1)