P87C51FB-4B,557 NXP Semiconductors, P87C51FB-4B,557 Datasheet - Page 16

• Manufacturer Part Number: P87C51FB-4B,557
• Manufacturer: NXP Semiconductors

Philips Semiconductors
2000 Aug 07
80C51 8-bit microcontroller family
8K–64K/256–1K OTP/ROM/ROMless, low voltage (2.7V–5.5V),
low power, high speed (33MHz)
T2EX PIN
OSC
T2 PIN
OSC
T2 PIN
12
TRANSITION
DETECTOR
12
C/T2 = 0
C/T2 = 1
C/T2 = 0
C/T2 = 1
EXEN2
TR2
Figure 4. Timer 2 in Auto-Reload Mode (DCEN = 0)
CONTROL
Figure 5. Timer 2 Auto Reload Mode (DCEN = 1)
CONTROL
TR2
(DOWN COUNTING RELOAD VALUE)
CONTROL
(UP COUNTING RELOAD VALUE)
RELOAD
RCAP2L
FFH
TL2
16
(8-BITS)
RCAP2L
RCAP2H
TL2
FFH
TH2
(8-BITS)
OVERFLOW
RCAP2H
TH2
8XC51RA+/RB+/RC+/RD+/80C51RA+
T2EX PIN
8XC51FA/FB/FC/80C51FA
EXF2
TF2
COUNT
DIRECTION
1 = UP
0 = DOWN
TOGGLE
TF2
Product specification
EXF2
INTERRUPT
8XC54/58
INTERRUPT
SU00730
TIMER 2
SU00067