User`s guide

3.1 EB164 Bcache Interface

The 21164 controls the backup cache (Bcache) array (see Figure 3–1). The

data bus (data<127:0>), check bus (data_check<15:0>), tag_dirty, and

tag_ctl_par signals are shared with the system interface.

Figure 3–1 EB164 Bcache Array

21164

index<19:4>

idle_bc

index<22:20>

Bcache

Data

Array

MK−2306−18

Bcache Size

Jumpers (3)

index<22:20>

sense_dis_l

tag_ram_oe

tag_ram_we

data_ram_oe

data_ram_we

Microprocessor

eb164.7eb164.2

data<127:0>

tag_data<29:20>

tag_valid

tag_dirty

tag_ctl_par

data_check<15:0>

tag_data_par

tag_data<38:30>

(h,l)data_ram_oe_l

(h,l)data_ram_we_l

tag_ram_oe_l

tag_ram_we_l

SRAM

Tag

Array

(From CIA Chip)

eb164.6

Buffers

eb164.6

(h,l)sense_dis

3–2 Functional Description