Functional Overview
3.7.2 HPI Nonmultiplexed Mode
In nonmultiplexed mode, a host with separate address/data buses can access the HPI16 data register (HPID)
via the HD 16-bit bidirectional data bus, and the address register (HPIA) via the 23-bit HA address bus. The
host initiates the access with the strobe signals (HDS1, HDS2, HCS) and controls the direction of the access
with the HR/W signal. The HPI16 can stall host accesses via the HRDY signal. Note that the HPIC register
is not available in nonmultiplexed mode since there are no HCNTL signals available. All host accesses initiate
a DMA read or write access. Figure 3−10 shows a block diagram of the HPI16 in nonmultiplexed mode.
HOST
HPI16
PPD[15:0]
DATA[15:0]
HPID[15:0]
HINT
DMA
Address[22:0]
HCNTL0
V
CC
HCNTL1
HBIL
HAS
R/W
HR/W
54xx
CPU
Data Strobes
HDS1, HDS2, HCS
HRDY
READY
Figure 3−10. Host-Port Interface — Nonmultiplexed Mode
Address (Hex)
0000
Reserved
005F
0060
DARAM0
1FFF
2000
DARAM1
3FFF
4000
†
DARAM2
5FFF
6000
†
DARAM3
7FFF
8000
†
DARAM4
9FFF
A000
Reserved
FFFF
†
Reserved on 5404 devices
Figure 3−11. HPI Memory Map
35
November 2001 − Revised April 2004
SPRS007D
TI [ TEXAS INSTRUMENTS ]
