I wondering what happens if an int from another source of VDP VBLANK appears and while the bios int routine is running a VDP interrupts kick in. Sequence:
1) Device A request an int: H.KEYI execute but at this pojnt no VDP int is requested.
2) H.TIMI execute but in the exact time the BIOS check if int is coming by VDP by reading S#0 the VDP request an interrupt.
3) because reading S#0 reset the int bit this will be read as inactive so no further processing occours.
Am i wrong or In this way the VDP int is lost?
The only way i can avoid this is checking other sources of interrupts on step (1) and preventing H.TIMI to execute if there are other devices.
Is there another way?
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