Freescale Semiconductor DSP56366 - Manual (Page 43)

PARALLEL HOST INTERFACE (HDI08)
DSP56366 24-Bit Digital Signal Processor User Manual, Rev. 4
Freescale Semiconductor 2-9
2.7 PARALLEL HOST INTERFACE (HDI08)
The HDI08 provides a fast, 8-bit, parallel data port that may be connected directly to the host bus. The
HDI08 supports a variety of standard buses and can be directly connected to a number of industry standard
microcomputers, microprocessors, DSPs, and DMA hardware.
Table 2-9 Host Interface
Signal Name Type
State during
Reset
Signal Description
H0 – H7 Input/
output
Host Data — When HDI08 is programmed to interface a nonmultiplexed
host bus and the HI function is selected, these signals are lines 0 – 7 of the
bidirectional, tri-state data bus.
HAD0 – HAD7 Input/
output
Host Address/Data — When HDI08 is programmed to interface a
multiplexed host bus and the HI function is selected, these signals are lines
0 – 7 of the address/data bidirectional, multiplexed, tri-state bus.
PB0 – PB7 Input, output, or
disconnected
GPIO
disconnected
Port B 0–7 — When the HDI08 is configured as GPIO, these signals are
individually programmable as input, output, or internally disconnected.
The default state after reset for these signals is GPIO disconnected.
These inputs are 5 V tolerant.
HA0 Input GPIO
disconnected
Host Address Input 0 — When the HDI08 is programmed to interface a
nonmultiplexed host bus and the HI function is selected, this signal is line 0
of the host address input bus.
HAS/HAS Input Host Address Strobe — When HDI08 is programmed to interface a
multiplexed host bus and the HI function is selected, this signal is the host
address strobe (HAS) Schmitt-trigger input. The polarity of the address
strobe is programmable, but is configured active-low (HAS) following reset.
PB8 Input, output, or
disconnected
Port B 8 — When the HDI08 is configured as GPIO, this signal is individually
programmed as input, output, or internally disconnected.
The default state after reset for this signal is GPIO disconnected.
This input is 5 V tolerant.
HA1 Input GPIO
disconnected
Host Address Input 1 — When the HDI08 is programmed to interface a
nonmultiplexed host bus and the HI function is selected, this signal is line 1
of the host address (HA1) input bus.
HA8 Input Host Address 8 — When HDI08 is programmed to interface a multiplexed
host bus and the HI function is selected, this signal is line 8 of the host
address (HA8) input bus.
PB9 Input, output, or
disconnected
Port B 9 — When the HDI08 is configured as GPIO, this signal is individually
programmed as input, output, or internally disconnected.
The default state after reset for this signal is GPIO disconnected.
This input is 5 V tolerant.