Motorola MVME187 User Manual

Page of 173
Multiprocessor Support
4-21
4
Network I/O Error Codes
187Bug returns an error code if an attempted network operation is 
unsuccessful. 
Multiprocessor Support
The MVME187 dual-port RAM feature makes the shared RAM 
available to remote processors as well as to the local processor. This 
can be done by either of the following two methods:
The Multiprocessor Control Register (MPCR) Method
The Global Control and Status Register (GCSR) Method
Either method can be enabled/disabled by the ENV command as 
its Remote Start Switch Method (refer to Appendix A). 
Multiprocessor Control Register (MPCR) Method
A remote processor can initiate program execution in the local 
MVME187 dual-port RAM by issuing a remote GO command 
using the Multiprocessor Control Register (MPCR). 
The MPCR, located at shared RAM location of $3000 offset from the 
base address the debugger loads it at, contains one of two words 
used to control communication between processors. The MPCR 
contents are organized as follows:
Base Address + $3000
*
N/A N/A N/A (MPCR)