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SCSI Controller
5-3
NCR53C9X SCSI Controller
There follows a brief description of the FSC registers. A detailed
programming description of the device is beyond the scope of this manual
and the user should refer to the bibliography at the rear of this document.
Command Register
The Command Register is a double-buffered register that allows two
commands to be written to the FSC consecutively. Bit 7 controls the
enabling of DMA operations and bits 6:0 provide a command code. Within
the command code, bits 6:4 control the operating mode, of which only one
can be selected at any time.
Bit 7
Enable DMA
0 = DMA Mode Disabled
1 = DMA Mode Enabled
Bit 6:4
Select Mode, see Table 5-2
An interrupt is generated if an invalid mode for the FSC is specified by bits
6:4, or if the command is not supported. Table 5-2 shows the commands
selectable using bits 6:0.
0x788000
24
Clock Conversion Register
W
0x788000
28
Test Mode
W
0x788000
2C
Configuration 2 Register
R/W
0x788000
30
Configuration 3 Register
R/W
0x788000
38
Transfer Counter High Register
R/W
Address
Register
Access
Table 5-1 FSC Register Set (Continued)
S3GX_TRMBook Page 3 Friday, September 19, 1997 11:39 am
Summary of Contents for SPARCbook 3 series
Page 8: ...viii S3GX_TRMBook Page viii Friday September 19 1997 11 39 am...
Page 44: ...2 16 The SPARC CPU SBus Controller S3GX_TRMBook Page 16 Friday September 19 1997 11 39 am...
Page 76: ...5 8 SCSI Controller DMA Support S3GX_TRMBook Page 8 Friday September 19 1997 11 39 am...
Page 146: ...9 28 MODEM Class 2 Fax Command Set S3GX_TRMBook Page 28 Friday September 19 1997 11 39 am...
Page 180: ...11 30 Display Interface RAMDAC S3GX_TRMBook Page 30 Friday September 19 1997 11 39 am...
Page 216: ...Index vi S3GX_TRMBook Page vi Friday September 19 1997 11 39 am...