Cherry-picking firmware changes only for Lynx support

Updating header comments

Better blocksize detection, cleanups

Cart_Reader/Cart_Reader.ino

@@ -183,7 +183,7 @@ template<class T> int EEPROM_readAnything(int ee, T& value) {
 #define rotate_to_change_STR 15
 #define press_to_select_STR 16
 
-// This arrays holds the most often uses strings
+// This array holds the most often used strings
 constexpr char string_press_button0[] PROGMEM = "Press Button...";
 constexpr char string_sd_error1[] PROGMEM = "SD Error";
 constexpr char string_did_not_verify3[] PROGMEM = "did not verify";
@@ -288,7 +288,7 @@ boolean root = 0;
 boolean filebrowse = 0;
 
 // Common
-// 21 chars for SNES ROM name, one char for termination
+// 21 chars for ROM name, one char for termination
 char romName[22];
 unsigned long sramSize = 0;
 int romType = 0;
@@ -456,7 +456,7 @@ uint32_t calculateCRC(char* fileName, char* folder, unsigned long offset) {
 /******************************************
    CRC Functions for Atari, Fairchild, Ody2, Arc, etc. modules
  *****************************************/
-#if (defined(ENABLE_ODY2) || defined(ENABLE_ARC) || defined(ENABLE_FAIRCHILD) || defined(ENABLE_MSX) || defined(ENABLE_POKE) || defined(ENABLE_2600) || defined(ENABLE_5200) || defined(ENABLE_7800) || defined(ENABLE_C64) || defined(ENABLE_VECTREX) || defined(ENABLE_NES))
+#if (defined(ENABLE_ODY2) || defined(ENABLE_ARC) || defined(ENABLE_FAIRCHILD) || defined(ENABLE_MSX) || defined(ENABLE_POKE) || defined(ENABLE_2600) || defined(ENABLE_5200) || defined(ENABLE_7800) || defined(ENABLE_C64) || defined(ENABLE_VECTREX) || defined(ENABLE_NES) || defined(ENABLE_LYNX))
 
 void printCRC(char* checkFile, uint32_t* crcCopy, unsigned long offset) {
   uint32_t crc = calculateCRC(checkFile, folder, offset);
@@ -1091,10 +1091,11 @@ constexpr char modeItem22[] PROGMEM = "Casio Loopy";
 constexpr char modeItem23[] PROGMEM = "Commodore 64";
 constexpr char modeItem24[] PROGMEM = "Atari 5200";
 constexpr char modeItem25[] PROGMEM = "Atari 7800";
-constexpr char modeItem26[] PROGMEM = "Vectrex";
-constexpr char modeItem27[] PROGMEM = "Flashrom Programmer";
-constexpr char modeItem28[] PROGMEM = "Self Test (3V)";
-constexpr char modeItem29[] PROGMEM = "About";
+constexpr char modeItem26[] PROGMEM = "Atari Lynx";
+constexpr char modeItem27[] PROGMEM = "Vectrex";
+constexpr char modeItem28[] PROGMEM = "Flashrom Programmer";
+constexpr char modeItem29[] PROGMEM = "Self Test (3V)";
+constexpr char modeItem30[] PROGMEM = "About";
 
 static const char* const modeOptions[] PROGMEM = {
 #ifdef ENABLE_GBX
@@ -1172,16 +1173,20 @@ static const char* const modeOptions[] PROGMEM = {
 #ifdef ENABLE_7800
   modeItem25,
 #endif
-#ifdef ENABLE_VECTREX
+#ifdef ENABLE_LYNX
   modeItem26,
 #endif
-#ifdef ENABLE_FLASH
+#ifdef ENABLE_VECTREX
   modeItem27,
 #endif
-#ifdef ENABLE_SELFTEST
+#ifdef ENABLE_FLASH
   modeItem28,
 #endif
-  modeItem29, FSTRING_RESET
+#ifdef ENABLE_SELFTEST
+  modeItem29,
+#endif
+  modeItem30,
+  FSTRING_RESET
 };
 
 uint8_t pageMenu(const __FlashStringHelper* question, const char* const* menuStrings, uint8_t entryCount, uint8_t default_choice = 0) {
@@ -1385,6 +1390,13 @@ void mainMenu() {
       break;
 #endif
 
+#ifdef ENABLE_LYNX
+    case SYSTEM_MENU_LYNX:
+      setup_LYNX();
+      return lynxMenu();
+      break;
+#endif    
+
 #ifdef ENABLE_VECTREX
     case SYSTEM_MENU_VECTREX:
       setup_VECTREX();
@@ -3583,6 +3595,9 @@ void loop() {
 #ifdef ENABLE_7800
   case CORE_7800: return a7800Menu();
 #endif
+#ifdef ENABLE_LYNX
+  case CORE_LYNX: return lynxMenu();
+#endif
 #ifdef ENABLE_VECTREX
   case CORE_VECTREX: return vectrexMenu();
 #endif

Cart_Reader/Config.h

@@ -89,6 +89,13 @@
 
 /****/
 
+/* [ Atari LYNX --------------------------------------------------- ]
+*/
+
+//#define ENABLE_LYNX
+
+/****/
+
 /* [ Benesse Pocket Challenge W ----------------------------------- ]
 */
 

Cart_Reader/LYNX.ino

@@ -0,0 +1,263 @@
+//******************************************
+// ATARI LYNX MODULE
+//******************************************
+//
+// For use with SNES-Lynx adapter
+// +----+
+// |  1 |- GND
+// |  2 |- D3
+// |  3 |- D2
+// |  4 |- D4
+// |  5 |- D1
+// |  6 |- D5
+// |  7 |- D0
+// |  8 |- D6
+// |  9 |- D7
+// | 10 |- /OE
+// | 11 |- A1
+// | 12 |- A2
+// | 13 |- A3
+// | 14 |- A6
+// | 15 |- A4
+// | 16 |- A5
+// | 17 |- A0
+// | 18 |- A7
+// | 19 |- A16
+// | 20 |- A17
+// | 21 |- A18
+// | 22 |- A19
+// | 23 |- A15
+// | 24 |- A14
+// | 25 |- A13
+// | 26 |- A12
+// | 27 |- /WE
+// | 28 |- A8
+// | 29 |- A9
+// | 30 |- A10
+// | 31 |- VCC
+// | 32 |- AUDIN
+// | 33 |- VCC
+// | 34 |- SWVCC
+// +----+
+//
+// By @partlyhuman
+// This implementation would not be possible without the invaluable
+// documentation on
+// https://atarilynxvault.com/
+// by Igor (@theatarigamer) of K-Retro Gaming / Atari Lynx Vault
+// and the reference implementation of the Lynx Cart Programmer Pi-Hat
+// https://bitbucket.org/atarilynx/lynx/src/master/
+// by Karri Kaksonen (whitelynx.fi) and Igor as well as countless contributions
+// by the Atari Lynx community
+//
+// Version 1.0
+// Future enhancements
+// 1. EEPROM read/write
+// 2. Homebrew flash cart programming
+//
+#ifdef ENABLE_LYNX
+
+#pragma region DEFS
+
+#define LYNX_HEADER_SIZE 64
+#define LYNX_WE 8
+#define LYNX_OE 9
+#define LYNX_AUDIN 46
+#define LYNX_BLOCKADDR 2048UL
+#define LYNX_BLOCKCOUNT 256UL
+// Includes \0
+static const char LYNX[5] = "LYNX";
+
+// Cart information
+static bool lynxUseAudin;
+static uint16_t lynxBlockSize;
+
+#pragma region LOWLEVEL
+
+void setup_LYNX() {
+  setVoltage(VOLTS_SET_5V);
+
+  // Address pins output
+  // A0-7, A8-A16 (A11 doesn't exist)
+  DDRF = 0xff;
+  DDRK = 0xff;
+  DDRL = 0xff;
+
+  // Data pins input
+  DDRC = 0x00;
+
+  // Control pins output
+  // CE is tied low, not accessible
+  pinMode(LYNX_WE, OUTPUT);
+  pinMode(LYNX_OE, OUTPUT);
+  pinMode(LYNX_AUDIN, OUTPUT);
+  digitalWrite(LYNX_WE, HIGH);
+  digitalWrite(LYNX_OE, HIGH);
+  digitalWrite(LYNX_AUDIN, HIGH);
+
+  strcpy(romName, LYNX);
+  mode = CORE_LYNX;
+}
+
+static void dataDir_LYNX(byte direction) {
+  DDRC = (direction == OUTPUT) ? 0xff : 0x00;
+}
+
+static uint8_t readByte_LYNX(uint32_t addr, uint8_t audin = 0) {
+  digitalWrite(LYNX_OE, HIGH);
+  PORTF = addr & 0xff;
+  PORTK = (addr >> 8) & 0xff;
+  PORTL = ((addr >> 16) & 0b111) | (audin << 3);
+  digitalWrite(LYNX_OE, LOW);
+  delayMicroseconds(20);
+  uint8_t data = PINC;
+  digitalWrite(LYNX_OE, HIGH);
+  return data;
+}
+
+#pragma region HIGHLEVEL
+
+static bool detectBlockSize_LYNX() {
+  lynxUseAudin = false;
+  lynxBlockSize = 0;
+
+  int i;
+  uint8_t block[LYNX_BLOCKADDR];
+  for (i = 0; i < LYNX_BLOCKADDR; i++) {
+    block[i] = readByte_LYNX(i, 0);
+  }
+
+  for (i = 0; i < LYNX_BLOCKADDR; i++) {
+    // If any differences are detected when AUDIN=1,
+    // AUDIN is used to bankswitch
+    // meaning we also use the maximum block size
+    // (1024kb cart / 256 blocks = 4kb block bank switched between two
+    // lower/upper 2kb blocks)
+    if (block[i] != readByte_LYNX(i, 1)) {
+      lynxUseAudin = true;
+      lynxBlockSize = 2048;
+      return true;
+    }
+  }
+
+  // Use the already-dumped 2KB to detect mirroring in a small sample
+  // Valid cart sizes of 128kb, 256kb, 512kb / 256 blocks
+  // = block sizes of 512b, 1024b, 2048b
+  const size_t DETECT_BYTES = 128;
+  for (i = 0; i < DETECT_BYTES; i++) {
+    if (block[i] != block[i + 256]) {
+      lynxBlockSize = max(lynxBlockSize, 512);
+    }
+    if (block[i] != block[i + 512]) {
+      lynxBlockSize = max(lynxBlockSize, 1024);
+    }
+    if (block[i] != block[i + 1024]) {
+      lynxBlockSize = max(lynxBlockSize, 2048);
+    }
+  }
+
+  return (lynxBlockSize > 0);
+}
+
+static bool detectCart_LYNX() {
+  // Could omit logging to save a few bytes
+  display_Clear();
+  println_Msg(F("Identifying..."));
+  if (!detectBlockSize_LYNX()) {
+    print_STR(error_STR, false);
+    display_Update();
+    wait();
+    resetArduino();
+  }
+  print_Msg(F("AUDIN="));
+  print_Msg(lynxUseAudin);
+  print_Msg(F(" BLOCK="));
+  println_Msg(lynxBlockSize);
+  display_Update();
+}
+
+static void writeHeader_LYNX() {
+  char header[LYNX_HEADER_SIZE] = {};
+  // Magic number
+  strcpy(header, LYNX);
+  // Cart name (dummy)
+  strcpy(header + 10, LYNX);
+  // Manufacturer (dummy)
+  strcpy(header + 42, LYNX);
+  // Version
+  header[8] = 1;
+  // Bank 0 page size
+  header[4] = lynxBlockSize & 0xff;
+  // Bank 1 page size
+  header[5] = (lynxBlockSize >> 8) & 0xff;
+  // AUDIN used
+  header[59] = lynxUseAudin;
+  // TODO detect EEPROM?
+  // header[60] = lynxUseEeprom;
+  myFile.write(header, LYNX_HEADER_SIZE);
+}
+
+static void readROM_LYNX() {
+  uint8_t block[lynxBlockSize];
+  uint32_t i;
+
+  dataDir_LYNX(INPUT);
+
+  // The upper part of the address is used as a block address
+  // There are always 256 blocks, but the size of the block can vary
+  // So outer loop always steps through block addresses
+
+  const uint32_t upto = LYNX_BLOCKCOUNT * LYNX_BLOCKADDR;
+  for (uint32_t blockAddr = 0; blockAddr < upto; blockAddr += LYNX_BLOCKADDR) {
+    draw_progressbar(blockAddr, upto);
+    blinkLED();
+
+    if (lynxUseAudin) {
+      // AUDIN bank switching uses a 4kb block split to 2 banks
+      for (i = 0; i < lynxBlockSize / 2; i++) {
+        block[i] = readByte_LYNX(blockAddr + i, 0);
+      }
+      for (; i < lynxBlockSize; i++) {
+        block[i] = readByte_LYNX(blockAddr + i - (lynxBlockSize / 2), 1);
+      }
+    } else {
+      for (i = 0; i < lynxBlockSize; i++) {
+        block[i] = readByte_LYNX(i + blockAddr);
+      }
+    }
+
+    myFile.write(block, lynxBlockSize);
+  }
+  draw_progressbar(upto, upto);
+}
+
+#pragma region MENU
+
+static const char* const menuOptionsLYNX[] PROGMEM = {FSTRING_READ_ROM,
+                                                      FSTRING_RESET};
+
+void lynxMenu() {
+  size_t menuCount = sizeof(menuOptionsLYNX) / sizeof(menuOptionsLYNX[0]);
+  convertPgm(menuOptionsLYNX, menuCount);
+  uint8_t mainMenu = question_box(F("LYNX MENU"), menuOptions, menuCount, 0);
+  display_Clear();
+  display_Update();
+
+  switch (mainMenu) {
+    case 0:
+      sd.chdir("/");
+      createFolderAndOpenFile(LYNX, "ROM", romName, "lnx");
+      detectCart_LYNX();
+      writeHeader_LYNX();
+      readROM_LYNX();
+      myFile.close();
+      sd.chdir("/");
+      compareCRC("lynx.txt", 0, true, LYNX_HEADER_SIZE);
+      print_STR(done_STR, true);
+      display_Update();
+      wait();
+      break;
+  }
+}
+
+#endif

Cart_Reader/OSCR.h

@@ -214,6 +214,9 @@ enum CORES: uint8_t {
 # ifdef ENABLE_7800
   CORE_7800,
 # endif
+# ifdef ENABLE_LYNX
+  CORE_LYNX,
+# endif
 # ifdef ENABLE_VECTREX
   CORE_VECTREX,
 # endif
@@ -302,6 +305,9 @@ enum SYSTEM_MENU: uint8_t {
 # if defined(ENABLE_7800)
   SYSTEM_MENU_7800,
 # endif
+# if defined(ENABLE_LYNX)
+  SYSTEM_MENU_LYNX,
+# endif
 # if defined(ENABLE_VECTREX)
   SYSTEM_MENU_VECTREX,
 # endif