Improved auto-configuration, detect "Apple //e enhanced".

IIe and //e enhanced are now separately detected and the font type is
automatically adjusted. The manual config switch for enhanced/unenhanced
fonts is removed. Overriding is still possible by setting the machine type
to "IIe" vs "IIe enhanced". #12

Author: ThorstenBr

.gitignore

@@ -1,5 +1,7 @@
 *.gch
 *.pyc
+*.lst
+*.bin
 _BUILD/PICO
 _BUILD/PICO2
 _BUILD/RELEASE

README.md

@@ -14,7 +14,7 @@ The project is a collaboration with Ralle Palaveev. His related hardware project
 * [A2DVI Hardware](https://github.com/rallepalaveev/A2DVI)
 
 The hardware is based on the PICO controller board.
-Both, original **PICO (RP2040)** and newer **PICO2 (RP2350)** mouldes are supported.
+Both, original **PICO (RP2040)** and newer **PICO2 (RP2350)** modules are supported.
 Separate firmware is provided for the two PICO variants.
 
 ![PICO_vs_PICO2](images/PICO_PICO2.jpg)
@@ -67,14 +67,15 @@ The A2DVI firmware tries to auto-detect your machine type - and adjusts various
 This also automatically adjusts the character set, if the current selection does not match the machine (with firmware >= v1.1):
 
 * When an Apple IIe is detected, but an Apple II font is selected, it switches to "Apple IIe US character set".
+* When an "Apple //e enhanced" is detected, then the "enhanced" variant of the font is used. Otherwise, for the "unenhanced IIe" the "unenhanced" fonts are used (with firmware >= v1.4).
 * When an Apple II is detected, but an Apple IIe font is selected, it switches to "Apple II+ US character set".
 
 If you do not want the automatic font switching (i.e. you want to use an Apple II font on the IIe), then disable the auto-detection by setting a *fixed* machine type.
 
-If your A2DVI is installed in a specific/fixed machine, it's recommended to set the configuration to a fixed type.
+If your A2DVI is installed in a specific/fixed machine, it's recommended to set "machine type" to the matching fixed type.
 
 ## Rendering Options
-* **Monochrome Mode**: configures the display of monochrom video modes. Selects display as black & white, green or amber (the most popular 1980s CRT types).
+* **Monochrome Mode**: configures the display of monochrome video modes. Selects display as black & white, green or amber (the most popular 1980s CRT types).
 * **Color Mode**: configures the display of color video modes. Selects "color" or "monochrome". When "monochrome" is selected, then all video modes are in monochrome.
 * **Scan Lines**: enables an effect to mimic the look of original CRT screens with scan lines.
 * **Analog Rendering Effects**: configures the rendering of double-LORES and double-HIRES video modes.
@@ -99,8 +100,9 @@ Included fonts for Apple IIe:
 
 * **US**, **UK**, **French**, **German**, **Italian**, **Spanish**, **Swedish/Finnish**, **Hebrew**, **Pravetz/Cyrillic**
 
-* The IIe fonts are "*enhanced character sets*" (include "mouse text characters" required for the "*enhanced* //e").
-There is a separate configuration option to disable "enhanced fonts": this replaces the mousetext characters with normal characters, like on an original "*unenhanced* Apple //e".
+* For the Apple IIe the "enhanced" or "unenhanced" variant of the IIe font is used - according to the machine type ("Apple IIe" vs "Apple //e enhanced").
+The machine is either auto-detected, or can be set manually.
+(The difference between the "*enhanced*" and "*unenhanced*" fonts are the graphical "mouse text characters", which only the "Apple //e enhanced" supported.)
 
 Included fonts for Apple II:
 
@@ -164,7 +166,7 @@ Connect the single pin on the A2DVI card to the language switch signal "ALTCHR",
 
 ## Video7 Support
 Video7 provided additional color text and video modes for the Apple IIe.
-Some (all?) of these modes were also available with other video cards, like the "Apple Extended 80 column Text/AppleColor Card".
+Some of these modes were also available with other video cards, like the "Apple Extended 80 column Text/AppleColor Card".
 
 A2DVI supports these extended video modes - even if your Apple IIe only has a standard 80 column card (and no extended video card).
 
@@ -177,7 +179,7 @@ The extra video modes:
 
 The following photo shows the difference of the default vs enhanced DHGR video mode (as supported by DazzleDraw).
 This video mode provides a mix of 140x192 pixels in 16 colors (just like default DHGR),
-but uses an unused 8th data bit to switich to a 560pixel/line monochrome resolution for a block of 7 bits:
+but uses an unused 8th data bit to switch to a 560pixel/line monochrome resolution for a block of 7 bits:
 
 ![Video7](images/A2DVI_Video7_DHGR.jpg)
 
@@ -237,7 +239,7 @@ The A2DVI firmware supports the font selection protocol of ROMX/ROMXe devices.
 
 * ROMX supports selecting between 16 different fonts.
 * A2DVI maps the 16 fonts selected by ROMX to A2DVI's 16 custom font slots. So you can upload and change those 16 fonts as you wish.
-* When ROMX selectes an empty custom font slot (1-16), then one of the built-in fonts (1-16) is used instead.
+* When ROMX selects an empty custom font slot (1-16), then one of the built-in fonts (1-16) is used instead.
 
 # Photos
 Here are some photos showing A2DVI in action - using the DVI/HDMI connection.
@@ -284,7 +286,7 @@ Firmware updates of an A2DVI card are easy and safe:
 * **Flash** (permanent) vs temporary configuration.
 * **Card registers** for configuration.
 * **Configuration menu**.
-* **Debug monitor** (Apple II video softswitches, 6502 CPU state).
+* **Debug monitor** (Apple II video soft switches, 6502 CPU state).
 * **PICO2 (RP2350) support**.
 * **Analog rendering effects** for Double-HIRES/Double-LORES (optional).
 * **ROMX font selection**.

firmware/applebus/businterface.c

@@ -43,8 +43,8 @@ static inline void __time_critical_func(machine_auto_detection)(uint32_t address
     if(current_machine == MACHINE_AUTO)
     {
         if((apple_memory[0x0403] == 0xD8) && (apple_memory[0x404] == 0xE5)) {        // "Xe" = ROMXe
-            detected_machine = MACHINE_IIE;
-            set_machine(MACHINE_IIE);
+            detected_machine = MACHINE_IIE_ENH;
+            set_machine(MACHINE_IIE_ENH);
         } else if((apple_memory[0x0412] == 0xC5) && (apple_memory[0x0413] == 0xD8)) {// "EX" = ROMX
             detected_machine = MACHINE_II;
             set_machine(MACHINE_II);
@@ -54,8 +54,8 @@ static inline void __time_critical_func(machine_auto_detection)(uint32_t address
             set_machine(MACHINE_IIGS);
 #endif
         } else if((apple_memory[0x416] == 0xAF) && (apple_memory[0x0417] == 0xE5)) { // "/e" = Apple //e Enhanced
-            detected_machine = MACHINE_IIE;
-            set_machine(MACHINE_IIE);
+            detected_machine = MACHINE_IIE_ENH;
+            set_machine(MACHINE_IIE_ENH);
         } else if((apple_memory[0x413] == 0xE5) && (apple_memory[0x0415] == 0xDD)) { // "e ]" = Apple //e Unenhanced
             detected_machine = MACHINE_IIE;
             set_machine(MACHINE_IIE);

firmware/config/config.c

@@ -38,7 +38,7 @@ volatile compat_t  detected_machine = MACHINE_AUTO;
 volatile compat_t  cfg_machine = MACHINE_AUTO;
 volatile compat_t  current_machine = MACHINE_AUTO;
 volatile bool      language_switch = false; // false: main/local char set, true: alternate char set (normally fixed to US default)
-volatile bool      enhanced_font_enabled;
+volatile bool      unenhance_font; // switch to explicitly "unenhance" a font (by removing the mouse text characters)
 volatile uint8_t   reload_charsets = 4;
 
 uint8_t            cfg_videx_selection = 0; //0:DISABLED
@@ -76,7 +76,7 @@ struct __attribute__((__packed__)) config_t
     uint8_t  alt_charset;   // selection for alternate video ROM (usually fixed to US charset)
 
     uint8_t  input_switch_mode;
-    uint8_t  enhanced_font_enabled;
+    uint8_t  OBSOLETE_enhanced_font_enabled; // no longer used (replaced by MACHINE_IIE_ENH)
     uint8_t  video7_enabled;
     uint8_t  debug_lines_enabled;
 
@@ -155,28 +155,47 @@ void __time_critical_func(set_machine)(compat_t machine)
 {
     switch(machine)
     {
+        case MACHINE_IIE:
+        case MACHINE_IIE_ENH:
+            internal_flags &= ~IFLAGS_IIGS_REGS;
+            internal_flags |=  IFLAGS_IIE_REGS;
+            break;
+#ifdef MACHINE_IIGS
+        case MACHINE_IIGS:
+            internal_flags &= ~IFLAGS_IIE_REGS;
+            internal_flags |=  IFLAGS_IIGS_REGS;
+            break;
+#endif
         case MACHINE_AUTO:
         case MACHINE_AGAT7:
         case MACHINE_AGAT9:
         case MACHINE_BASIS:
         case MACHINE_PRAVETZ:
         case MACHINE_II:
+        default:
             internal_flags &= ~(IFLAGS_IIGS_REGS|IFLAGS_IIE_REGS);
             break;
+    }
 
-        case MACHINE_IIE:
-            internal_flags &= ~IFLAGS_IIGS_REGS;
-            internal_flags |= IFLAGS_IIE_REGS;
-            break;
-
-        case MACHINE_IIGS:
-            internal_flags &= ~IFLAGS_IIE_REGS;
-            internal_flags |= IFLAGS_IIGS_REGS;
-            break;
-
-        default:
-            break;
+    if (machine == MACHINE_IIE)
+    {
+        // we need to "unenhance" the fonts for the IIe (unenhanced)
+        if (!unenhance_font)
+        {
+            unenhance_font = true;
+            reload_charsets |= 3;
+        }
     }
+    else
+    {
+        // all other machines, including "//e enhanced": leave fonts unchanged
+        if (unenhance_font)
+        {
+            unenhance_font = false;
+            reload_charsets |= 3;
+        }
+    }
+
     if ((current_machine == MACHINE_AUTO)&&
         (machine != MACHINE_AUTO))
     {
@@ -244,7 +263,7 @@ void DELAYED_COPY_CODE(config_load_charsets)(void)
         // local font
         memcpy32(character_rom, character_roms[check_valid_font(cfg_local_charset)], CHARACTER_ROM_SIZE);
 
-        if (!enhanced_font_enabled)
+        if (unenhance_font)
         {
             // unenhance the font, by overwriting the mousetext characters
             memcpy32(&character_rom[0x40*8], &character_rom[0], 0x20*8);
@@ -256,7 +275,7 @@ void DELAYED_COPY_CODE(config_load_charsets)(void)
         // alternate fixed US font (with language switch)
         memcpy32(&character_rom[0x800], character_roms[check_valid_font(cfg_alt_charset)], CHARACTER_ROM_SIZE);
 
-        if (!enhanced_font_enabled)
+        if (unenhance_font)
         {
             // unenhance the font, by overwriting the mousetext characters
             memcpy32(&character_rom[0x800+0x40*8], &character_rom[0x800], 0x20*8);
@@ -293,6 +312,11 @@ void config_load(void)
     }
 
     cfg_machine = (cfg->machine_type <= MACHINE_MAX_CFG) ? cfg->machine_type : MACHINE_AUTO;
+    if ((cfg_machine == MACHINE_IIE)&&(cfg->OBSOLETE_enhanced_font_enabled != 0))
+    {
+        // convert old config setting
+        cfg_machine = MACHINE_IIE_ENH;
+    }
     set_machine(cfg_machine);
 
     SET_IFLAG(cfg->scanline_emulation,   IFLAGS_SCANLINEEMU);
@@ -313,7 +337,7 @@ void config_load(void)
     config_setflags();
 
     input_switch_mode = cfg->input_switch_mode;
-    enhanced_font_enabled   = (cfg->enhanced_font_enabled != 0);
+    unenhance_font = (cfg_machine == MACHINE_IIE);
 
     color_mode = (cfg->color_mode <= 2) ? cfg->color_mode : 0;
 
@@ -344,7 +368,7 @@ void config_load_defaults(void)
     set_machine(detected_machine);
 
     input_switch_mode       = ModeSwitchLangCycle;
-    enhanced_font_enabled   = true;
+    unenhance_font          = false;
 
     cfg_local_charset       = DEFAULT_LOCAL_CHARSET;
     cfg_alt_charset         = DEFAULT_ALT_CHARSET;
@@ -380,7 +404,6 @@ void DELAYED_COPY_CODE(config_save)(void)
     new_config->local_charset           = cfg_local_charset;
     new_config->alt_charset             = cfg_alt_charset;
     new_config->input_switch_mode       = input_switch_mode;
-    new_config->enhanced_font_enabled   = enhanced_font_enabled;
 
     // update flash
     config_flash_write(cfg, (uint8_t *)new_config, new_config_size);

firmware/config/config.h

@@ -33,12 +33,13 @@ typedef enum
 {
     MACHINE_II      = 0,
     MACHINE_IIE     = 1,
-    MACHINE_IIGS    = 2,             // currently not supported
+    MACHINE_IIE_ENH = 2,
     MACHINE_AGAT7   = 3,
     MACHINE_AGAT9   = 4,
     MACHINE_BASIS   = 5,
     MACHINE_PRAVETZ = 6,
     MACHINE_MAX_CFG = MACHINE_PRAVETZ, // valid maximum option for config, otherwise "AUTO" is assumed
+//  MACHINE_IIGS    = 7,             // currently not supported
     MACHINE_INVALID = 0xfe,
     MACHINE_AUTO    = 0xff
 } compat_t;
@@ -81,7 +82,6 @@ extern          uint8_t  cfg_videx_selection;
 extern volatile uint8_t  reload_charsets;
 
 extern volatile bool language_switch;
-extern volatile bool enhanced_font_enabled;
 
 typedef enum {
     COLOR_MODE_BW    = 0,