Motorola MVME187 As the initialization proceeds, the execution path comes to the prompt routine

Models: MVME187

1 173
Download 173 pages 29 Kb
Page 105
Image 105
3.As the initialization proceeds, the execution path comes to the "prompt" routine.

Multiprocessor Support

3.As the initialization proceeds, the execution path comes to the "prompt" routine.

Before sending the prompt, this routine places an R in the MPCR to indicate that initialization is complete. Then the prompt is sent.

ÐIf no terminal is connected to the port, the MPCR is still polled to see whether an external processor requires control to be passed to the dual-port RAM.

ÐIf a terminal does respond, the MPCR is polled for the same purpose while the serial port is being polled for user input.

ÐAn ASCII G placed in the MPCR by a remote processor indicates that the Go Direct type of transfer is requested.

ÐAn ASCII B in the MPCR indicates that breakpoints are to be armed before control is transferred (as with the GO command).

In either sequence, an E is placed in the MPCR to indicate that execution is underway just before control is passed to RAM. (Any remote processor could examine the MPCR contents.)

4.If the code being executed in dual-port RAM is to reenter the debug monitor, a TRAP #496 call using function $0063 (SYSCALL .RETURN) returns control to the monitor with a new display prompt.

Note that every time the debug monitor returns to the prompt, an R is moved into the MPCR to indicate that control can be transferred once again to a specified RAM location.

4

4-23

Page 105
Image 105
Motorola MVME187 manual As the initialization proceeds, the execution path comes to the prompt routine