Compaq 21264 - Manual (Page 178)

5–36 Internal Processor Registers Alpha 21264/EV67 Hardware Reference Manual
Cbox CSRs and IPRs
BC_TAG_DDM_RISE_EN[0] Enables the update of the 21264/EV67 Bcache tag outputs based on
the rising edge of the forwarded clock.
BC_CLKFWD_ENABLE[0] Enable clock forwarding on the Bcache interface.
BC_RCV_MUX_CNT_PRESET[0:1] Initial value for the Bcache clock forwarding unload pointer FIFO.
BC_LATE_WRITE_UPPER[0] Duplicate CSR.
SYS_DDM_FALL_EN[0] Enables the update of the 21264/EV67 system outputs based on the
falling edge of the system forwarded clock.
SYS_DDM_RISE_EN[0] Enables the update of the 21264/EV67 system outputs based on the
rising edge of the system forwarded clock.
SYS_CLKFWD_ENABLE[0] Enables clock forwarding on the system interface.
SYS_RCV_MUX_CNT_PRESET[0:1] Initial value for the system clock forwarding unload pointer FIFO.
SYS_CLK_DELAY[0:1] Delay of 0 to 2 phases between the forwarded clock out and
address/data.
SYS_DDMR_ENABLE[0] Enables the rising edge of the system forwarded clock (always
enabled).
SYS_DDMF_ENABLE[0] Enables the falling edge of the system forwarded clock (always
enabled).
BC_DDM_FALL_EN[0] Enables update of data/address on the rising edge of the system for-
warded clock.
BC_DDM_RISE_EN[0] Enables the update of data/address on the falling edge of the system
forwarded clock.
BC_CLKFWD_ENABLE Duplicate CSR.
BC_RCV_MUX_CNT_PRESET[0:1] Duplicate CSR.
BC_CLK_DELAY[0:1] Duplicate CSR.
BC_DDMR_ENABLE Duplicate CSR.
BC_DDMF_ENABLE Duplicate CSR.
SYS_DDM_FALL_EN Duplicate CSR.
SYS_DDM_RISE_EN Duplicate CSR.
SYS_CLKFWD_ENABLE Duplicate CSR.
SYS_RCV_MUX_CNT_PRESET[0:1] Duplicate CSR.
SYS_CLK_DELAY[0:1] Duplicate CSR.
SYS_DDMR_ENABLE Duplicate CSR.
SYS_DDMF_ENABLE Duplicate CSR.
BC_DDM_FALL_EN Duplicate CSR.
BC_DDM_RISE_EN Duplicate CSR.
BC_CLKFWD_ENABLE Duplicate CSR.
BC_RCV_MUX_CNT_PRESET[0:1] Duplicate CSR.
Table 5–24 Cbox WRITE_ONCE Chain Order (Continued)
Cbox WRITE_ONCE Chain Description