C8051F80X_14 Datasheet, PDF (212/251 Pages) Silicon Laboratories – Mixed Signal ISP Flash MCU Family

C8051F80x-83x
T0M
Pre-scaled Clock
0
SYSCLK
0
1
1
T0
Crossbar
TR0
GATE0
TMOD
GCT TGCT T
A / 11A / 00
T T MM T T MM
E110E010
1
0
IT01CF
IIIIIIII
NNNNNNNN
11110000
PSSSPSSS
LLLLLLLL
210 210
TCLK
TL0
(5 bits)
TH0
(8 bits)
TF1
TR1
TF0
Interrupt
TR0
IE1
IT1
IE0
IT0
INT0
IN0PL _XOR
Figure 28.1. T0 Mode 0 Block Diagram
28.1.2. Mode 1: 16-bit Counter/Timer
Mode 1 operation is the same as Mode 0, except that the counter/timer registers use all 16 bits. The coun-
ter/timers are enabled and configured in Mode 1 in the same manner as for Mode 0.
28.1.3. Mode 2: 8-bit Counter/Timer with Auto-Reload
Mode 2 configures Timer 0 and Timer 1 to operate as 8-bit counter/timers with automatic reload of the start
value. TL0 holds the count and TH0 holds the reload value. When the counter in TL0 overflows from all
ones to 0x00, the timer overflow flag TF0 in the TCON register is set and the counter in TL0 is reloaded
from TH0. If Timer 0 interrupts are enabled, an interrupt will occur when the TF0 flag is set. The reload
value in TH0 is not changed. TL0 must be initialized to the desired value before enabling the timer for the
first count to be correct. When in Mode 2, Timer 1 operates identically to Timer 0.
Both counter/timers are enabled and configured in Mode 2 in the same manner as Mode 0. Setting the
TR0 bit (TCON.4) enables the timer when either GATE0 in the TMOD register is logic 0 or when the input
signal INT0 is active as defined by bit IN0PL in register IT01CF (see Section “18.3. INT0 and INT1 External
Interrupts” on page 111 for details on the external input signals INT0 and INT1).
212
Rev. 1.0