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29 September 1997 – Subject To Change
Internal Processor Registers
5–65
External Interface Control (CBU) IPRs
5.3.4 CBU Configuration #2 (CBOX_CONFIG2) Register (FF FFF0 0188)
CBOX_CONFIG2 is a read/write register that controls Bcache and memory, the per-
formance counters, and the debug test port. Figure 5–51 and Table 5–29 describe the
CBOX_CONFIG2 register format.
Figure 5–51 CBU Configuration #2 (CBOX_CONFIG2) Register
Table 5–29 CBU Configuration #2 Register Fields
(Sheet 1 of 3)
Name
Extent
Type
Description
Reserved
<03:00> RW,0 Reserved to DIGITAL. Must be zero (MBZ).
BC_REG_REG
<04>
RW,1 When set, this bit indicates that the Bcache is built from
REG/REG SSRAM. When clear, it indicates that the Bcache
is built from REG/FT SSRAM.
This bit is used to delay the deassertion of data_ram_oe_l
during system Bcache read transactions (for example, Bcache
victims or system probes that require data movement).
DBG_SEL
<5>
RW,0 Selects the Cbox debug information for the debug port.
DBG_SEL=0 DBG_SEL=1
biu_trans
head merge
NOP cmd
tail merge
rty or abt
RMW tail
wr_now
stxc
ri_wr req
fmc != NOP
PCA007
31
00
63
07
11
06
10
05
MBZ
08
MBZ
04 03
14 13
MBZ
BC_REG_REG
PM1_MUX<2:0>
DBG_SEL
MBZ
PM0_MUX<2:0>
BC_THREE_MISS
32
15
SYSRD_DCLK_EN