AT&T 3B2/300 Technical Reference Manual page 516

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Address Spectrum
The VCACHE card provides "pulse points" to control the operation of the cache. By accessing the
addresses shown in Figure 3-80, the listed operations are performed.
ADDRESS OPERATION
ACCESS
OxlCOOOOO
READ ID REGISTER READ
Ox1C00004 TURN VCACHE OFF READ/WRITE
OxlCOOOOB TURN VCACHE ON READ/WRITE
OxlCOOOOC
FLUSH ENTIRE CACHE
READ/WRITE
OxlCOOOlO TURN DIAGNOSTIC MODE OFF READ/WRITE
Ox1C00014 TURN DIAGNOSTIC MODE ON READ/WRITE
Ox1C00018 UNUSED READ/WRITE
OxlCOOOlC FLUSH DATA CACHE READ/WRITE
Ox1C02000
RAM READ/WRITE
I
Ox1C03FFF
Figure 3-80: CM522A VCACHE Card Address Map
ID Register
The VCACHE card provides a one byte ID Register at byte O of address OxlCOOOOO. Reading this
register will return the ID of OxOO.
CM522A Equipped Device Table Data
The following table shows the Equipped Device Table (EDT) data for a CM522A Card. A value of
0 means NO; a value of 1 means YES. The indirect device (indir_dev) is only applicable to systems
equipped with Small Computer System Interface (SCSI). The request queue size (rq_size) and the
completion queue size (cq_size) are SCSI software defined values. As such, the rq_size and cq_size
values may differ between versions of SCSI software.
EDT ITEM DATA
IDENTIFICATION CODE (ID_code)
Ox FEOO
DEVICE NAME (dev_name)
VCACHE
REQUEST QUEUE SIZE (rq_size)
Ox 00
COMPLETION QUEUE SIZE (cq_size)
Ox 00
BOOT DEVICE (booLdev)
0
WORD SIZE (word_size)
0
BOARD SIZE (brcLsize) 0
SMART BOARD (smrLbrd)
0
CONSOLE CAPABILITY (cons_cap)
0
CONSOLE FILE (cons_file) 0
INDIRECT DEVICE (indir_dev) 0
FUNCTIONAL DESCRIPTION 3-263