Motorola DSP96002 User Manual

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DSP96002 USER’S MANUAL

MOTOROLA

In the DSP96002 side, the X/Y/P Memory Write interrupt vector should point to a routine that
first reads HRX to get the address A, stores A in an address pointer Rn, and then again reads
HRX to retrieve the data D and store D into the DSP96002 memory location pointed by Rn.

The host processor may test TRDY to see if both A and D were removed from the input double
buffer (TX/HRX).

Figure 7-22 shows a flowchart for X Memory Write.

The following code is executed by the master processor. The R3 register contains the address needed for

selecting the "TX register write and X Memory Write interrupt" host function in the slave HI, as defined in

Figure 7-12. The R4 register contains the address needed for reading the ICS register of the slave HI. The

R1 register contains the target X memory address. The R0 register contains the data to be written to the

target X memory address. The master executes the following instructions:

DSP

96002

MASTER PROCESSOR DSP

96002

SLAVE PROCESSOR

Semaphore Control Semaphore Register (SEM)

1.Set Semaphore in slave’s
Semaphore Register using
BSET Instruction.
2.If Semaphore was set before
repeat step 1 else continue

X Memory Write Interrupt/Status Register

1.Check if the slave’s TX
register is empty (TXDE=1)
2.If TXDE=0
repeat step 1 else continue
3.Write the X memory address
to the slave’s "TX register
+ X Memory Write Interrupt"

(

—

–

S=0,

—

–

A=1, A5-A2=0010)

4.Check if the slave’s TX
register is empty (TXDE=1)
5.If TXDE=0
repeat step 4 else continue
6.Write the data
to the slave’s TX register
+ X Memory Write Interrupt

(

—

–

S=0,

—

–

A=1, A5-A2=0010) X Memory Write Interrupt Pend

Start Interrupt Processing

1.Move contents of Host HRX
Register to AGU Register:
When was interrupt serviced? MOVEP X:HRX,Rn
2.Move contents of Host HRX
If both address and data are Register to X Memory Addr:
read from HRX, TRDY = 1. MOVEP X:HRX,X:(Rn)

Figure 7-22. X Memory Write Procedure