4-52 DSP56012 User’s Manual MOTOROLA

Parallel Host Interface
Host Interface (HI)

Figure 4-27 Host Command

$17—DEFAULT
VIEW FROM HOST VIEW FROM DSP56012
1. WRITE CVR WITH DESIRED HV.
HC
HOST COMMAND
2. SET HC = 1. 3. HCP IS SET UNTIL INTERRUPT IS ACKNOWLEDGED.
4. HOST COMMAND IS MASKED UNTIL HCIE = 1.
5. WHEN THE HOST COMMAND interrupt IS ACKNOWLEDGED, THE HC
BIT IS CLEARED BY THE HOST COMMAND LOGIC. HC CAN BE READ AS
A STATUS BIT.
HCP
HOST COMMAND PENDING
interrupt VECTOR TABLE
HCIE
HOST COMMAND INTERRUPT ENABLE
P:$007E AVAILABLE FOR HOST COMMAND
FAST INTERRUPT
OR
LONG INTERRUPT
$1 COMMAND VECTOR
REGISTER (CVR)
HC—HOST COMMAND (STATUS)
P:$0000
HOST COMMAND DEFAULT VECTOR
P:$0034
AVAILABLE FOR HOST COMMAND
AVAILABLE FOR HOST COMMAND
interrupt VECTOR
ADDRESS = HV x 2
$1 COMMAND
VECTOR
REGISTER (CVR)
1HOST VECTOR (HV)
70
0
5
X:$FFE8 HOST CONTROL
REGISTER (HCR)
0HF3 HF2 HTIE HRIE
70
00
654321
1
X:$FFE9 HOST STATUS
REGISTER (HSR)
DMA HF1 HF0 HTDE HRDF
70
00
654321
1
AA0336
0HOST VECTOR (HV)
70
0
5

Note: When using the SAI and DAX

peripherals, do not use interrupt vector

addresses P:$0040–$004A, $0050,

$0052, and $0056.