nec/pc9801.cpp: fix upper ARTIC port reads

This commit is contained in:
angelosa 2024-11-26 17:08:27 +01:00
parent 9c86cae581
commit 6cc52bd96a

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@ -1066,9 +1066,15 @@ void pc9801vm_state::dma_access_ctrl_w(offs_t offset, u8 data)
// ARTIC device // ARTIC device
/*
* [0] read bits 15-0 of the counter device
* [1] read bits 23-8 of the counter device
*
* FreeDOS(98) Kernel will test [1] a whole lot during HMA allocation
*/
uint16_t pc9801vm_state::timestamp_r(offs_t offset) uint16_t pc9801vm_state::timestamp_r(offs_t offset)
{ {
return (m_maincpu->total_cycles() >> (16 * offset)); return (m_maincpu->total_cycles() >> (8 * offset));
} }
void pc9801vm_state::artic_wait_w(u8 data) void pc9801vm_state::artic_wait_w(u8 data)