HD64570 Datasheet, PDF (107/469 Pages) Hitachi Semiconductor – Serial Communications Adaptor

Bit 7 (T3IRQ: Timer Channel 3 Interrupt Request):
T3IRQ = 0: Timer channel 3 is not requesting a T3IRQ interrupt.
T3IRQ = 1: Timer channel 3 is requesting a T3IRQ interrupt.
Bit 6 (T2IRQ: Timer Channel 2 Interrupt Request):
T2IRQ = 0: Timer channel 2 is not requesting a T2IRQ interrupt.
T2IRQ = 1: Timer channel 2 is requesting a T2IRQ interrupt.
Bit 5 (T1IRQ: Timer Channel 1 Interrupt Request):
T1IRQ = 0: Timer channel 1 is not requesting a T1IRQ interrupt.
T1IRQ = 1: Timer channel 1 is requesting a T1IRQ interrupt.
Bit 4 (T0IRQ: Timer Channel 0 Interrupt Request):
T0IRQ = 0: Timer channel 0 is not requesting a T0IRQ interrupt.
T0IRQ = 1: Timer channel 0 is requesting a T0IRQ interrupt.
Bit 3−Bit 0: Reserved. These bits always read 0 .
Rev. 0, 07/98, page 91 of 453