
W83977TF
PRELIMINARY
Publication Release Date: March 1998
-120-
Revision 0.62
CRF3 (Default 0x00)
Bit 7 - 6: Reserved. Return zero when read.
Bit 5 - 0: Device's IRQ status.
These bits indicate the IRQ status of the individual device. The device's IRQ status
by their source device and is cleared by writing a 1. Writing a 0 has no effect.
Bit 5: MOUIRQSTS. MOUSE IRQ status.
Bit 4: KBCIRQSTS. KBC IRQ status.
Bit 3: PRTIRQSTS. printer port IRQ status.
Bit 2: FDCIRQSTS. FDC IRQ status.
Bit 1: URAIRQSTS. UART A IRQ status.
Bit 0: URBIRQSTS. UART B IRQ status.
CRF4 (Default 0x00)
Bit 7 - 4: Reserved. Return zero when read.
Bit 2: FDCTRAPSTS. FDC trap status.
= 0
FDC is now in the sleeping state.
= 1
FDC is now in the working state due to any FDC access, any IRQ, any DMA
acknowledge, and any enabling of the motor enable bits in the DOR register.
Bit 1: URATRAPSTS. UART A trap status.
= 0
UART A is now in the sleeping state.
= 1
UART A is now in the working state due to any UART A access, any IRQ, the
receiver begins receiving a start bit, the transmitter shift register begins transmitting a
start bit, and any transition on MODEM control input lines.
Bit 0: URBTRAPSTS. UART B trap status.
= 0
UART B is now in the sleeping state.
= 1
UART B is now in the working state due to any UART B access, any IRQ, the
receiver begins receiving a start bit, the transmitter shift register begins transmitting
a start bit, and any transition on MODEM control input lines.
bit is set
Bit 3 - 0: Enable bits of the
SMI
generation due to the device's idleness.
These bits enable the generation of an
SMI
interrupt due to the expiration of the device's idle
timer. These 4 bits control the printer port, FDC, UART A, and UART B
SMI
logics respectively.
Bit 3: PRTIDLEN.
= 0
disable the generation of an
SMI
interrupt due to printer port's idleness.
Bit 2: FDCIDLEN.
= 1
enable the generation of an
SMI
interrupt due to printer port's idleness.
= 0
disable the generation of an
SMI
interrupt due to FDC's idleness.
= 1
enable the generation of an
SMI
interrupt due to FDC's idleness.