W83877TF Datasheet, PDF (131/154 Pages) Winbond – I/O chip disk drive adapter

W83877TF
URBCNT7 - URBCNT0 (Bit 7 - bit 0): UART B idle timer count.
This register is used to specify the initial value of UART B idle timer. Once UART B enters the
working state (that is, after any access to this device, any IRQ, and any external input), the power
down machine of UART B reloads this count value and the idle timer counts down. When the timer
counts down to zero, UART B enters the power down state ,i.e., sleeping state. If this register is set to
00H, the power down function will be invalid. The time resolution of this value is minute or second,
which is defined by the TMIN_SEL bit of CR3A. Note that (1). this register is valid only when the
power management function of UART B is enabled, that is, CHIPPME=1 (CR32 bit 7) and
URBPME=1 (CR32 bit 0), (2). If the register is set to 00H, UART B will remain in the current
state(working or sleeping).
8.2.42 Configuration Register 37 (CR37), default=00H
When the device is in Extended Function mode and EFIR is 37H, the CR37 register can be accessed
through EFDR. The bit definitions are as follows:
765
43
21
0
FDCCNT0
FDCCNT1
FDCCNT2
FDCCNT3
FDCCNT4
FDCCNT5
FDCCNT6
FDCCNT7
FDCCNT7 - FDCCNT0 (Bit 7 - bit 0): FDC idle timer count.
This register is used to specify the initial value of FDC idle timer. Once FDC enters the working state
(that is, after any access to this device, any IRQ, and any external input), the power down machine of
FDC reloads this count value and the idle timer counts down. When the timer counts down to zero,
FDC enters the power down state ,i.e., sleeping state. If this register is set to 00H, the power down
function will be invalid. The time resolution of this value is minute or second, which is defined by the
TMIN_SEL bit of the CR3A. Note that (1). this register is valid only when the power management
function of FDC is enabled, that is, CHIPPME=1 (CR32 bit 7) and FDCPME=1 (CR32 bit 2), (2). If the
register is set to 00H, FDC will remain in the current state(working or sleeping).
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Publication Release Date: March 1998
Version 0.61