W83877ATG Nuvoton Technology Corporation of America, W83877ATG Datasheet - Page 151

• Manufacturer Part Number: W83877ATG
• Manufacturer: Nuvoton Technology Corporation of America

Specifications of W83877ATG

• Lead Free Status / RoHS Status: Supplier Unconfirmed

Bit 7 - bit 4 : Reserved, fixed at 0.
Bit 3 - bit 0 : Devices' idle status.
These bits indicate that the individual device's idle timer expires due to no I/O access, IRQ, and
external input to the device respectively. These 4 bits are controlled by the printer port, FDC, UART A,
and UART B power down machines individually. The bits are set/cleared by W83877ATF/ATG
automatically. Writing a 1 can also clear this bit, and writing a 0 has no effect.
PRTIDLSTS (Bit 3): printer port idle status.
FDCIDLSTS (Bit 2): FDC idle status.
URAIDLSTS (Bit 1): UART A idle status.
URBIDLSTS (Bit 0): UART B idle status.
0
1
0
1
0
1
0
1
printer port is now in the working state.
printer port is now in the sleeping state due to no printer port access, IRQ, DMA
acknowledge, and no transition on BUSY, ACK , PE, SLCT, and
FDC is now in the working state.
FDC is now in the sleeping state due to no FDC access, no IRQ, no DMA acknowledge,
and no enabling of the motor enable bits in the DOR register.
UART A is now in the working state.
UART A is now in the sleeping state due to no UART A access, no IRQ, the receiver is
now waiting for a start bit, the transmitter shift register is now empty, and no transition
on MODEM control input lines.
UART B is now in the working state.
UART B is now in the sleeping state due to no UART B access, no IRQ, the receiver is
now waiting for a start bit, the transmitter shift register is now empty, and no transition
on MODEM control input lines.
7
6
5
4
3
- 144 -
2
W83877ATF/W83877ATG
1
0
URBIDLSTS
URAIDLSTS
FDCIDLSTS
PRTIDLSTS
reserved
reserved
reserved
reserved
ERR pins.