W83977F-A Datasheet, PDF (38/182 Pages) Winbond – WINBOND I/O

W83977F-A/ W83977G-A/ W83977AF-A/ W83977AG-A
5.2.2 Status Register B (SB Register) (Read base address + 1)
This register is used to monitor several disk interface pins in PS/2 and Model 30 modes. In PS/2
mode, the bit definitions for this register are as follows:
765 4 3 ²¹ 0
11
MOT EN A
MOT EN B
WE
RDATA Toggle
WDATA Toggle
Drive SEL0
Drive SEL0 (Bit 5):
This bit indicates the status of DO REGISTER bit 0 (drive select bit 0).
WDATA Toggle (Bit 4):
This bit changes state at every rising edge of the WD output pin.
RDATA Toggle (Bit 3):
This bit changes state at every rising edge of the RDATA output pin.
WE (Bit 2):
This bit indicates the complement of the WE output pin.
MOT EN B (Bit 1)
This bit indicates the complement of the MOB output pin.
MOT EN A (Bit 0)
This bit indicates the complement of the MOA output pin.
In PS/2 Model 30 mode, the bit definitions for this register are as follows:
765 43 ²¹ 0
DRV2 (Bit 7):
0 A second drive has been installed
1 A second drive has not been installed
DSB (Bit 6):
-30
DSC
DSD
WE F/F
RDATA F/F
WD F/F
DSA
DSB
DRV2