bsnes-patches/v085/0014-Support-alternate-more-accurate-poll-timings.patch

   1 From 40c456dadd79cb2c94379fda8b41a4d0ba051ad1 Mon Sep 17 00:00:00 2001
   2 From: Ilari Liusvaara <ilari.liusvaara@elisanet.fi>
   3 Date: Sat, 7 Dec 2013 23:32:44 +0200
   4 Subject: [PATCH 14/27] Support alternate (more accurate) poll timings
   5
   6 ---
   7  snes/config/config.cpp     |  1 +
   8  snes/config/config.hpp     |  1 +
   9  snes/cpu/timing/joypad.cpp | 40 ++++++++++++++++++++++++++++++++++++++++
  10  snes/cpu/timing/timing.cpp | 16 ++++++++++++----
  11  snes/cpu/timing/timing.hpp |  1 +
  12  snes/snes.hpp              |  1 +
  13  6 files changed, 56 insertions(+), 4 deletions(-)
  14
  15 diff --git a/snes/config/config.cpp b/snes/config/config.cpp
  16 index 701af94c..206daae0 100755
  17 --- a/snes/config/config.cpp
  18 +++ b/snes/config/config.cpp
  19 @@ -13,6 +13,7 @@ Configuration::Configuration() {
  20    cpu.ntsc_frequency  = 21477272;  //315 / 88 * 6000000
  21    cpu.pal_frequency   = 21281370;
  22    cpu.wram_init_value = 0x55;
  23 +  cpu.alt_poll_timings = false;
  24
  25    smp.ntsc_frequency = 24607104;   //32040.5 * 768
  26    smp.pal_frequency  = 24607104;
  27 diff --git a/snes/config/config.hpp b/snes/config/config.hpp
  28 index 1f4d037c..dabde597 100755
  29 --- a/snes/config/config.hpp
  30 +++ b/snes/config/config.hpp
  31 @@ -10,6 +10,7 @@ struct Configuration {
  32      unsigned ntsc_frequency;
  33      unsigned pal_frequency;
  34      unsigned wram_init_value;
  35 +    bool alt_poll_timings;
  36    } cpu;
  37
  38    struct SMP {
  39 diff --git a/snes/cpu/timing/joypad.cpp b/snes/cpu/timing/joypad.cpp
  40 index 6a98de00..ae8e94f8 100755
  41 --- a/snes/cpu/timing/joypad.cpp
  42 +++ b/snes/cpu/timing/joypad.cpp
  43 @@ -29,4 +29,44 @@ void CPU::step_auto_joypad_poll() {
  44    }
  45  }
  46
  47 +//called every 128 clocks; see CPU::add_clocks()
  48 +void CPU::step_auto_joypad_poll_NEW(bool polarity) {
  49 +  if(status.auto_joypad_counter > 0 && status.auto_joypad_counter <= 34) {
  50 +    if(!status.auto_joypad_latch) {
  51 +      //FIXME: Is this right, busy flag goes on even if not enabled???
  52 +      if(status.auto_joypad_counter == 1)
  53 +        status.auto_joypad_active = true;
  54 +      if(status.auto_joypad_counter == 34)
  55 +        status.auto_joypad_active = false;
  56 +    } else {
  57 +      if(status.auto_joypad_counter == 1) {
  58 +        status.auto_joypad_active = true;
  59 +        input.port1->latch(1);
  60 +        input.port2->latch(1);
  61 +      }
  62 +      if(status.auto_joypad_counter == 3) {
  63 +        input.port1->latch(0);
  64 +        input.port2->latch(0);
  65 +      }
  66 +      if((status.auto_joypad_counter & 1) != 0 &&  status.auto_joypad_counter != 1) {
  67 +        uint2 port0 = input.port1->data();
  68 +        uint2 port1 = input.port2->data();
  69 +
  70 +        status.joy1 = (status.joy1 << 1) | (bool)(port0 & 1);
  71 +        status.joy2 = (status.joy2 << 1) | (bool)(port1 & 1);
  72 +        status.joy3 = (status.joy3 << 1) | (bool)(port0 & 2);
  73 +        status.joy4 = (status.joy4 << 1) | (bool)(port1 & 2);
  74 +      }
  75 +      if(status.auto_joypad_counter == 34)
  76 +        status.auto_joypad_active = false;
  77 +    }
  78 +    status.auto_joypad_counter++;
  79 +  }
  80 +  if(vcounter() >= (ppu.overscan() == false ? 225 : 240) && status.auto_joypad_counter == 0 && !polarity) {
  81 +    status.auto_joypad_latch = status.auto_joypad_poll;
  82 +    status.auto_joypad_counter = 1;
  83 +  }
  84 +}
  85 +
  86 +
  87  #endif
  88 diff --git a/snes/cpu/timing/timing.cpp b/snes/cpu/timing/timing.cpp
  89 index f1378f0c..d7cf24f3 100755
  90 --- a/snes/cpu/timing/timing.cpp
  91 +++ b/snes/cpu/timing/timing.cpp
  92 @@ -17,10 +17,18 @@ void CPU::add_clocks(unsigned clocks) {
  93
  94    step(clocks);
  95
  96 -  status.auto_joypad_clock += clocks;
  97 -  if(status.auto_joypad_clock >= 256) {
  98 -    status.auto_joypad_clock -= 256;
  99 -    step_auto_joypad_poll();
 100 +  if(config.cpu.alt_poll_timings) {
 101 +    bool opolarity = (status.auto_joypad_clock & 128);
 102 +    status.auto_joypad_clock = (status.auto_joypad_clock + clocks) & 0xFF;
 103 +    bool npolarity = (status.auto_joypad_clock & 128);
 104 +    if(opolarity != npolarity)
 105 +      step_auto_joypad_poll_NEW(opolarity);
 106 +  } else {
 107 +    status.auto_joypad_clock += clocks;
 108 +    if(status.auto_joypad_clock >= 256) {
 109 +      status.auto_joypad_clock -= 256;
 110 +      step_auto_joypad_poll();
 111 +    }
 112    }
 113
 114    if(status.dram_refreshed == false && hcounter() >= status.dram_refresh_position) {
 115 diff --git a/snes/cpu/timing/timing.hpp b/snes/cpu/timing/timing.hpp
 116 index 6c225dab..bf15a727 100755
 117 --- a/snes/cpu/timing/timing.hpp
 118 +++ b/snes/cpu/timing/timing.hpp
 119 @@ -22,3 +22,4 @@ alwaysinline bool irq_test();
 120
 121  //joypad.cpp
 122  void step_auto_joypad_poll();
 123 +void step_auto_joypad_poll_NEW(bool polarity);
 124 diff --git a/snes/snes.hpp b/snes/snes.hpp
 125 index 37ed1feb..4e3ba64c 100755
 126 --- a/snes/snes.hpp
 127 +++ b/snes/snes.hpp
 128 @@ -1,6 +1,7 @@
 129  #ifndef SNES_HPP
 130  #define SNES_HPP
 131  #define BSNES_SUPPORTS_ADV_BREAKPOINTS
 132 +#define BSNES_SUPPORTS_ALT_TIMINGS
 133
 134  namespace SNES {
 135    namespace Info {
 136 --
 137 2.15.0.rc1
 138