Registers – Rainbow Electronics AT89C5122 User Manual
Page 152

152
AT8xC5122/23
4202E–SCR–06/06
Registers
Timer/Counter Control Register
Reset Value = 0000 0000b
Table 88. TCON (S:88h)
7
6
5
4
3
2
1
0
TF1
TR1
TF0
TR0
IE1
IT1
IE0 IT0
Bit
Number
Bit
Mnemonic
Description
7
TF1
Timer 1 Overflow flag
Cleared by the hardware when processor vectors interrupt routine.
Set by the hardware when Timer 1 register overflows.
6
TR1
Timer 1 Run Control bit
Clear to turn off Timer/Counter 1.
Set to turn on Timer/Counter 1.
5
TF0
Timer 0 Overflow flag
Cleared by the hardware when processor vectors interrupt routine or by software
when the interrupt is disabled
Set by the hardware when Timer 0 register overflows.
4
TR0
Timer 0 Run Control bit
Clear to turn off Timer/Counter 0.
Set to turn on Timer/Counter 0.
3
IE1
Interrupt 1 Edge flag
Cleared by the hardware when interrupt is processed if edge-triggered (see IT1).
Set by the hardware when external interrupt is detected on the INT1# pin.
2
IT1
Interrupt 1 Type Control bit
Clear to select low level active (level triggered) for external interrupt 1 (INT1#).
Set to select falling edge active (edge triggered) for external interrupt 1.
1
IE0
Interrupt 0 Edge flag
Cleared by the hardware when interrupt is processed if edge-triggered (see IT0).
Set by the hardware when external interrupt is detected on INT0# pin.
0
IT0
Interrupt 0 Type Control bit
Clear to select low level active (level triggered) for external interrupt 0 (INT0#).
Set to select falling edge active (edge triggered) for external interrupt 0.