How is the binding done between SEGA 315-5250 and the Z80/M68000 CPUs?

[jotego]

The code suggests that device SEGA 315-5250 is able to interrupt the Z80 and M68000 CPUs in system 16B because of the members m_68kint_callback and m_zint_callback. But for the life of me that I cannot see where the binding is done and to which interrupt line. Nor can I see how the Z80 can access that same device to read data after its interrupted. It does not appear in the memory map in the S16B driver either.

Is this connected at all?

[cuavas]

Those outputs are only used on the Sega X Board, and only for one of the two timers. It’s connected where you’d expect: https://github.com/mamedev/mame/blob/mame0256/src/mame/sega/segaxbd.cpp#L1683

[jotego]

Thank so much. That makes sense now.