Return to previous page ｜ Return to menu ｜ Go to next page

6. Usage restrictions

■ SCSI interrupt problem

Communication between
SSBug and sound board is done by SCSI (level 1 auto vector). For this reason, when the sound board side becomes interrupt level 1 or higher for a long time, the dialog “No response” is displayed.


If the sound board hangs up at this time, it stops while the SCSI bus is occupied, so the Macintosh also stops working. As a result, the window opens while trying to display the "No response" dialog, but the resource cannot be loaded because the SCSI bus is occupied, and the window stops without displaying the contents. Become.
In such a case, wait for the SCSI bus to be released once by doing one of the following, and then try again.


■ Vector that SSBug hooks

Exception vectors used by SSBug (rewritten during user execution) are as follows. 
    reset
bus error
address error
illegal instruction
zero divide
chk instruction
trapv instruction
privillege violation
trace
uninitialized interrupt
spurious interrupt
level 1 auto vector
level 7 auto vector
Programs that dynamically rewrite these vectors or reference them at runtime are not guaranteed to work under SSBug. However, there is no problem if you have a static vector table.

Return to previous page ｜ Return to menu ｜ Go to next page