From fdc854c0c2aee18ae7b098a7e4523e7a738b9347 Mon Sep 17 00:00:00 2001
From: Thomas Harte <thomas.harte@gmail.com>
Date: Mon, 13 Jun 2016 21:49:59 -0400
Subject: [PATCH] Fixed tone channels; made an attempt at loading PRGs that are
 supposed to go into RAM.

---
 Components/6560/6560.cpp  | 17 +++++++++++------
 Components/6560/6560.hpp  |  2 ++
 Machines/Vic-20/Vic20.cpp | 11 +++++++++--
 Machines/Vic-20/Vic20.hpp |  2 +-
 4 files changed, 23 insertions(+), 9 deletions(-)

diff --git a/Components/6560/6560.cpp b/Components/6560/6560.cpp
index 182cf8cd3..4d1abce6a 100644
--- a/Components/6560/6560.cpp
+++ b/Components/6560/6560.cpp
@@ -312,30 +312,32 @@ void MOS6560::set_graphics_value(uint8_t value, uint8_t colour_value)
 
 void MOS6560::update_audio()
 {
-	_speaker.run_for_cycles(_cycles_since_speaker_update >> 4);
-	_cycles_since_speaker_update &= 15;
+	_speaker.run_for_cycles(_cycles_since_speaker_update >> 2);
+	_cycles_since_speaker_update &= 3;
 }
 
 #pragma mark - Audio
 
-MOS6560Speaker::MOS6560Speaker()
+MOS6560Speaker::MOS6560Speaker() :
+	_volume(0),
+	_control_registers{0, 0, 0, 0},
+	_shift_registers{0, 0, 0, 0},
+	_counters{0, 1, 2, 0}
 {
 }
 
 void MOS6560Speaker::set_volume(uint8_t volume)
 {
 	_volume = volume;
-	printf("Volume: %d\n", volume);
 }
 
 void MOS6560Speaker::set_control(int channel, uint8_t value)
 {
 	_control_registers[channel] = value;
-	printf("Control %02x: %d\n", channel, value);
 }
 
 #define shift(r) _shift_registers[r] = (uint8_t)((_shift_registers[r] << 1) | (((_shift_registers[r]^0x80)&_control_registers[r]) >> 7));
-#define update(r, m) _counters[r]++; if((_counters[r] >> m) == 0xff) { shift(r); _counters[r] = _control_registers[r]&0x7f; }
+#define update(r, m) _counters[r]++; if((_counters[r] >> m) == 0x7f) { shift(r); _counters[r] = _control_registers[r]&0x7f; }
 
 void MOS6560Speaker::get_samples(unsigned int number_of_samples, int16_t *target)
 {
@@ -360,3 +362,6 @@ void MOS6560Speaker::skip_samples(unsigned int number_of_samples)
 		update(2, 0);
 	}
 }
+
+#undef shift
+#undef update
diff --git a/Components/6560/6560.hpp b/Components/6560/6560.hpp
index b8b66fc85..59a73d8f4 100644
--- a/Components/6560/6560.hpp
+++ b/Components/6560/6560.hpp
@@ -40,6 +40,8 @@ class MOS6560 {
 		uint16_t get_address();
 		void set_graphics_value(uint8_t value, uint8_t colour_value);
 
+		void synchronise() { update_audio(); }
+
 		void set_register(int address, uint8_t value);
 		uint8_t get_register(int address);
 
diff --git a/Machines/Vic-20/Vic20.cpp b/Machines/Vic-20/Vic20.cpp
index 1212c589f..5a60dcc1d 100644
--- a/Machines/Vic-20/Vic20.cpp
+++ b/Machines/Vic-20/Vic20.cpp
@@ -123,7 +123,14 @@ void Machine::add_prg(size_t length, const uint8_t *data)
 	{
 		_rom_address = (uint16_t)(data[0] | (data[1] << 8));
 		_rom_length = (uint16_t)(length - 2);
-		_rom = new uint8_t[length - 2];
-		memcpy(_rom, &data[2], length - 2);
+		if(_rom_address >= 0x1000 && _rom_address+_rom_length < 0x2000)
+		{
+			memcpy(&_screenMemory[_rom_address - 0x1000], &data[2], length - 2);
+		}
+		else
+		{
+			_rom = new uint8_t[length - 2];
+			memcpy(_rom, &data[2], length - 2);
+		}
 	}
 }
diff --git a/Machines/Vic-20/Vic20.hpp b/Machines/Vic-20/Vic20.hpp
index 3843d392a..6e9e09a85 100644
--- a/Machines/Vic-20/Vic20.hpp
+++ b/Machines/Vic-20/Vic20.hpp
@@ -100,7 +100,7 @@ class Machine: public CPU6502::Processor<Machine>, public CRTMachine::Machine, p
 
 		// to satisfy CPU6502::Processor
 		unsigned int perform_bus_operation(CPU6502::BusOperation operation, uint16_t address, uint8_t *value);
-		void synchronise() {}
+		void synchronise() { _mos6560->synchronise(); }
 
 		// to satisfy CRTMachine::Machine
 		virtual void setup_output(float aspect_ratio);