B-136
DSP56F801/803/805/807 User’s Manual
MOTOROLA
Preliminary
Application:
Date:
Programmer:
Sheet
C
B
1 of 10
Bits
Name
Description
8
HRMS
Host Request Mode Select
The Host mode Select (HRMS) bit controls the host request pins
7
HDDS
Host Dual Data Strobe
When the Host Dual Data Strobe (HDDS) bit is set, the HI8 operates in the Dual Data Strobe
Bus mode; a host bus with separated read and write data strobes. When cleared, the HI8
operates in the Single Strobe Bus mode, i.e. a Host bus with a single Data Strobe signal.
6
TDMAEN
DSP Side Transmit DMA Enable
The TDMAEN bit is used to enable DSP side Transmit DMA operations. When set, the on-chip
DMA controller handles transferring data between the HTX register and DSP memory. The
on-chip DMA controller must be appropriately configured to implement the desired data transfer.
5
RDMAEN
DSP Side Receive DMA Enable
The RDMAEN bit is used to enable DSP side Receive DMA operations. When set, the on-chip
DMA controller handles transferring data between the HRX register and DSP memory. The
on-chip DMA controller must be appropriately configured to implement the desired data transfer.
4
HF2
Host Flags 2 and 3
3HF3
The Host Flag 2 and Host Flag 3 (HF2 and HF3) bits are used as general purpose flags for
DSP-to-Host communication. HF2 and HF3 may be set or cleared by the DSP core. HF2 and
HF3 are reflected in the Interrupt Status Register (ISR) on the Host Side if they are modified by
the DSP software, the host processor can read the modified values by reading the ISR.
2
HCIE
Host Command Interrupt Enable
The HCIE bit is used to enable a DSP core interrupt when the HCP status bit in the HSR is set.
When cleared, HCP interrupts are disabled. When set, a Host Command Interrupt request
occurs if HCP is set. The interrupt address is determined by the Host Command Vector
Register. Cleared on hardware reset.
1
HTIE
Host Transmit Interrupt Enable
The HTIE bit is used to enable a DSP core interrupt when the Host Transmit Data Empty status
bit in the HSR is set. When cleared, HTDE interrupts are disabled. When set, a Host Transmit
Data Interrupt request occurs when the HTDE bit is set. It is cleared on hardware reset.
0
HRIE
Host Receive Interrupt Enable
The HRIE bit is used to enable a DSP core interrupt when the Host Receive Data Full (HRDF)
status bit in the Host Status Register (HSR) is set. When cleared, HRDF interrupts are disabled.
When set, a Host Receive Data Interrupt request occurs if the HRDF bit is also set. It is cleared
on hardware reset.
HI8 Host Control
Register (HCR)
$1FFFD8 + $0
Bits
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
Read
0
HRMS HDDS TDMAEN REDMAEN HF3 HF2 HCIE HTIE HRIE
Write
0
RESET
0
000
00
0
HI8 Host Control Register (HCR)
HI8
denotes Reserved Bits