hardie@sask.UUCP (04/22/87)
Is there a kind soul out there who knows how to use the interrupt system to catch 8520 timer interrupts? Spercifically, I want to be able to have a program that is interrupted 400-500 times a second and during the interrupt have a quick look at the parallel port and plot a couple of points in a bitmap. I can read the port no problem, but at the moment am using an awful busy loop to watch the timer. The solution should preferably use an absolute minimum of assembler code and maximize the amount of C. Thanks extremely. Pete Hardie ihnp4!sask!hardie
grr@cbmvax.cbm.UUCP (George Robbins) (04/26/87)
In article <701@sask.UUCP> hardie@sask.UUCP (Peter Hardie ) writes: > >Is there a kind soul out there who knows how to use the interrupt >system to catch 8520 timer interrupts? Spercifically, I want to be able >to have a program that is interrupted 400-500 times a second and during >the interrupt have a quick look at the parallel port >and plot a couple of points in a bitmap. Can you explain more about what you are trying to do? That seems like an extremely high interrupt rate for a non-dedicated system. It might be better to use the PC input to cause an interrupt when your external status changes, rather than watch it constantly. -- George Robbins - now working for, uucp: {ihnp4|seismo|rutgers}!cbmvax!grr but no way officially representing arpa: cbmvax!grr@seismo.css.GOV Commodore, Engineering Department fone: 215-431-9255 (only by moonlite)