Motorola 24-Bit Digital Signal Processor, DSP56000 - page 215

USING THE OnCE
MOTOROLA ON-CHIP EMULATION (OnCE) 10 - 23
The OnCE controller selects GDB as source for serial data.
6. ACK
7. CLK
10.11.3 Displaying X Memory Area Starting From Address XXXX
This command uses R0 to minimize serial traffic.
1. Send command WRITE PDB REGISTER, GO, no EX (01001001).
The OnCE controller selects PDB as destination for serial data.
2. ACK
3. Send the 24-bit DSP56K opcode: “MOVE R0,x:OGDB”
After 24 bits have been received the PDB register drives the PDB. The OnCE con-
troller releases the chip from the debug mode and the contents of R0 are loaded
in the GDB REGISTER. The signal that marks the end of the instruction returns the
chip to the debug mode.
4. ACK
5. Send command READ GDB REGISTER (10001001)
The OnCE controller selects GDB as source for serial data.
6. ACK
7. CLK
The external command controller generates 24 clocks that shift out the contents of
the GDB register. The value of R0 is thus saved and should be restored before ex-
iting the debug mode.
8. Send command WRITE PDB REGISTER, no GO, no EX (00001001)
OnCE controller selects PDB as destination for serial data.
9. ACK
10. Send the 24-bit DSP56K opcode: “MOVE #$xxxx,R0”
After 24 bits have been received, the PDB register drives the PDB. The OnCE con-
troller causes the processor to load the opcode.
11. ACK
12. Send command WRITE PDB REGISTER, GO, no EX (01001001)
The OnCE controller selects PDB as destination for serial data.
13. ACK
14. Send the 24-bit 2nd word of: “MOVE #$xxxx,R0” (the xxxx field).
After 24 bits have been received, the PDB register drives the PDB. The OnCE con-