Host Interface (HI08)
DSP56303 Technical Data, Rev. 11
Freescale Semiconductor
1-9
HA0
HAS/HAS
PB8
Input
Input or Output
Ignored Input
Host Address Input 0—When the HI08 is programmed to interface with a
nonmultiplexed host bus and the HI function is selected, this signal is line 0 of
the host address input bus.
Host Address Strobe—When the HI08 is programmed to interface with 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.
Port B 8—When the HI08 is configured as GPIO through the HI08 Port Control
Register, this signal is individually programmed as an input or output through the
HI08 Data Direction Register.
HA1
HA8
PB9
Input
Input or Output
Ignored Input
Host Address Input 1—When the HI08 is programmed to interface with a
nonmultiplexed host bus and the HI function is selected, this signal is line 1 of
the host address (HA1) input bus.
Host Address 8—When the HI08 is programmed to interface with a multiplexed
host bus and the HI function is selected, this signal is line 8 of the host address
(HA8) input bus.
Port B 9—When the HI08 is configured as GPIO through the HI08 Port Control
Register, this signal is individually programmed as an input or output through the
HI08 Data Direction Register.
HA2
HA9
PB10
Input
Input or Output
Ignored Input
Host Address Input 2—When the HI08 is programmed to interface with a
nonmultiplexed host bus and the HI function is selected, this signal is line 2 of
the host address (HA2) input bus.
Host Address 9—When the HI08 is programmed to interface with a multiplexed
host bus and the HI function is selected, this signal is line 9 of the host address
(HA9) input bus.
Port B 10—When the HI08 is configured as GPIO through the HI08 Port Control
Register, this signal is individually programmed as an input or output through the
HI08 Data Direction Register.
HCS/HCS
HA10
PB13
Input
Input or Output
Ignored Input
Host Chip Select—When the HI08 is programmed to interface with a
nonmultiplexed host bus and the HI function is selected, this signal is the host
chip select (HCS) input. The polarity of the chip select is programmable but is
configured active-low (HCS) after reset.
Host Address 10—When the HI08 is programmed to interface with a
multiplexed host bus and the HI function is selected, this signal is line 10 of the
host address (HA10) input bus.
Port B 13—When the HI08 is configured as GPIO through the HI08 Port Control
Register, this signal is individually programmed as an input or output through the
HI08 Data Direction Register.
HRW
HRD/HRD
PB11
Input
Input or Output
Ignored Input
Host Read/Write—When the HI08 is programmed to interface with a single-
data-strobe host bus and the HI function is selected, this signal is the Host
Read/Write (HRW) input.
Host Read Data—When the HI08 is programmed to interface with a double-
data-strobe host bus and the HI function is selected, this signal is the HRD
strobe Schmitt-trigger input. The polarity of the data strobe is programmable but
is configured as active-low (HRD) after reset.
Port B 11—When the HI08 is configured as GPIO through the HI08 Port Control
Register, this signal is individually programmed as an input or output through the
HI08 Data Direction Register.
Table 1-11.
Host Interface (Continued)
Signal Name
Type
State During
Reset1,2
Signal Description