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multibus: fixed regression on isbc202 #13594

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fulivi
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@fulivi fulivi commented Apr 15, 2025

Hi,
this commit fixes a regression on isbc202 emulation caused by cf67936, which removed ownership of multibus slots by multibus bus. By doing so it removed the propagation of clock down to cards.
iSBC202 was affected because it (probably) is the only multibus card in MAME that relies on clock to come from the bus.
Thanks.
--F.Ulivi

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Do you think this is the best approach? Would it be better to change the slot constructor to allow a clock frequency to be supplied rather than always using zero?

#define IPC_XTAL_Y1 19.6608_MHz_XTAL
constexpr auto IPC_XTAL_Y1 = 19.6608_MHz_XTAL;
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If you turn this into a global variable, it needs to have a constant address across an invocation and hence increases static data size. If it’s only used in a single function, you can make it a local variable.

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Aren't constexpr variables implicitly inline since C++17?

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3 participants