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cosmac: Fixed long branch instruction timing. [Curt Coder]

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Curt Coder 2019-05-10 17:06:33 +03:00
parent bd1f2dbac7
commit da5950d944
2 changed files with 0 additions and 9 deletions
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2
src/devices/cpu/cosmac/cosmac.cpp
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@ -1215,8 +1215,6 @@ void cosmac_device::long_branch(int taken)
// S1#1, S1#2 // S1#1, S1#2
R[P]++; R[P]++;
} }
m_icount -= CLOCKS_EXECUTE;
} }
void cosmac_device::lbr() { long_branch(1); } void cosmac_device::lbr() { long_branch(1); }

7
src/devices/video/cdp1861.cpp
View File

@ -34,12 +34,6 @@ Timing as it applies to the Studio II:
- At the end, the random number seed (not part of video drawing) gets - At the end, the random number seed (not part of video drawing) gets
updated and the interrupt routine ends. updated and the interrupt routine ends.
The current situation:
- For whatever reason, the CPU is taking 32 cycles to process the 14
pre-DMA instructions instead of the required 29 cycles. Therefore
the DMA timer is adjusted to fire 32*8 clocks after INT (every cycle
is 8 clocks).
**********************************************************************/ **********************************************************************/
#include "emu.h" #include "emu.h"
@ -175,7 +169,6 @@ void cdp1861_device::device_timer(emu_timer &timer, device_timer_id id, int para
} }
m_int_timer->adjust(screen().time_until_pos( SCANLINE_INT_END, 0)); m_int_timer->adjust(screen().time_until_pos( SCANLINE_INT_END, 0));
m_dma_timer->adjust(clocks_to_attotime(32*8)); // adjust DMA to occur exact number of cycle after INT - should be 29*8
} }
else else
{ {