CPC: save autoload .SCR

with a .BAS if needed

src/cpc_scr_simple_loader.h

@@ -0,0 +1,28 @@
+/* vim:expandtab:ts=2 sw=2:
+ */
+/**
+ * author : unknown
+ */
+static const unsigned char cpc_scr_simple_loader[] = {
+ 0x3a, 0xd0, 0xd7,  // C7D0 LD A,(D7D0)
+ 0xcd, 0x1c, 0xbd,  // C7D3 CALL BD1C ; Set screen mode
+ 0x21, 0xd1, 0xd7,  // C7D6 LD HL,D7D1
+ 0x46,              // C7D9 LD B,(HL)
+ 0x48,              // C7DA LD C,B
+ 0xcd, 0x38, 0xbc,  // C7DB CALL BC38 ; Set border
+ 0xaf,              // C7DE XOR A
+ 0x21, 0xd1, 0xd7,  // C7DF LD HL,D7D1
+ 0x46,              // C7E2 LD B,(HL)       <-------------------+
+ 0x48,              // C7E3 LD C,B                              |
+ 0xf5,              // C7E4 PUSH AF                             |
+ 0xe5,              // C7E5 PUSH HL                             |
+ 0xcd, 0x32, 0xbc,  // C7E6 CALL BC32 ; Set ink A to color B,C  |
+ 0xe1,              // C7E9 POP HL                              |
+ 0xf1,              // C7EA POP AF                              |
+ 0x23,              // C7EB INC HL                              |
+ 0x3c,              // C7EC INC A                               |
+ 0xfe, 0x10,        // C7ED CP &10                              |
+ 0x20, 0xf1,        // C7EF JZ NZ, C7E2      -------------------+
+ 0xc3, 0x18, 0xbb   // C7F1 JP BB18   ; Wait key
+
+};

src/cpcformats.c

@@ -29,6 +29,7 @@
 
 #include <stdlib.h>
 #include <string.h>
+#include <ctype.h>
 #include "global.h"
 #include "fileformats.h"
 #include "io.h"
@@ -607,6 +608,9 @@ void Load_SCR(T_IO_Context * context)
   free(cpc_ram);
 }
 
+#include "impdraw_loader.h"
+#include "cpc_scr_simple_loader.h"
+
 /**
  * Save Amstrad SCR file
  *
@@ -633,32 +637,43 @@ void Save_SCR(T_IO_Context * context)
   unsigned char r1 = 0;
   int cpc_mode;
   FILE* file;
-
+  int cpc_plus_pal = 0;
+  unsigned short load_address = 0xC000;
+  unsigned short exec_address = 0xC7D0;
+  int overscan;
+  byte cpc_hw_pal[16];
+  byte r12 = 0x0C | 0x30;
+  byte r13 = 0;
 
   switch(context->Ratio)
   {
     case PIXEL_WIDE:
     case PIXEL_WIDE2:
       cpc_mode = 0;
+      overscan = (context->Width * context->Height) > (16384 * 2);
       break;
     case PIXEL_TALL:
     case PIXEL_TALL2:
     case PIXEL_TALL3:
       cpc_mode = 2;
+      overscan = (context->Width * context->Height) > (16384 * 8);
       break;
     default:
       cpc_mode = 1;
+      overscan = (context->Width * context->Height) > (16384 * 4);
       break;
   }
-
+  if (overscan)
-  file = Open_file_write_with_alternate_ext(context, "pal");
-  if (file == NULL)
-    return;
-  if (!Write_byte(file, cpc_mode) || !Write_byte(file, 0) || !Write_byte(file, 0))
   {
-    fclose(file);
+    // format iMP v2
-    return;
+    load_address = 0x170;
+    // picture at 0x200
+    r12 = 0x0C | (0x200 >> 9);
+    r13 = (0x200 >> 1) & 0xff;
+    exec_address = 0; // BASIC program !
   }
+
+  CPC_set_HW_palette(context->Palette + 0x40);
   for (i = 0; i < 16; i++)
   {
     // search for the color in the HW palette (0x40-0x5F)
@@ -669,12 +684,28 @@ void Save_SCR(T_IO_Context * context)
     if (index >= 0x60)
     {
       GFX2_Log(GFX2_WARNING, "Save_SCR() color #%i not found in CPC HW palette.\n", i);
-      // TODO : set CPC Plus flag
+      cpc_plus_pal = 1;
       index = 0x54 - i; // default
     }
+    cpc_hw_pal[i] = index;
+    if (!CPC_is_CPC_old_color(context->Palette + i))
+      cpc_plus_pal = 1;
+  }
+
+  file = Open_file_write_with_alternate_ext(context, "pal");
+  if (file == NULL)
+    return;
+  CPC_write_AMSDOS_header(file, context->File_name, "pal", 2, 0x8809, 0x8809, 239);
+  if (!Write_byte(file, cpc_mode) || !Write_byte(file, 0) || !Write_byte(file, 0))
+  {
+    fclose(file);
+    return;
+  }
+  for (i = 0; i < 16; i++)
+  {
     for (j = 0; j < 12; j++)  // write the same color for the 12 frames
     {
-      Write_byte(file, index);
+      Write_byte(file, cpc_hw_pal[i]);
     }
   }
   // border
@@ -694,7 +725,7 @@ void Save_SCR(T_IO_Context * context)
   }
   fclose(file);
 
-  output = raw2crtc(context, cpc_mode, 7, &outsize, &r1, 0x0C, 0);
+  output = raw2crtc(context, cpc_mode, 7, &outsize, &r1, r12, r13);
   GFX2_Log(GFX2_DEBUG, "Save_SCR() output=%p outsize=%lu r1=$%02X\n", output, outsize, r1);
 
   if (output == NULL)
@@ -706,9 +737,80 @@ void Save_SCR(T_IO_Context * context)
   else
   {
     File_error = 0;
+    CPC_write_AMSDOS_header(file, context->File_name, "SCR", overscan ? 0 : 2, load_address, exec_address, overscan ? 32400 : outsize);
+    if (overscan)
+    {
+      // write iMPdraw loader
+      byte buffer[0x90];
+      memcpy(buffer, impdraw_loader, 0x90);
+      buffer[0x184 - 0x170] = 0x0e + cpc_mode;
+      buffer[0x18e - 0x170] = r1;
+      //buffer[0x190 - 0x170] = // R2 ?
+      buffer[0x192 - 0x170] = context->Height / 8;  // r6
+      //buffer[0x194 - 0x170] = // r7 ?
+      buffer[0x196 - 0x170] = r12;
+      buffer[0x198 - 0x170] = r13;
+      buffer[0x1ac - 0x170] = cpc_plus_pal;
+      if (!Write_bytes(file, buffer, 0x90))
+        File_error = 1;
+      output = realloc(output, 32400 - 0x90);
+      memset(output + outsize, 0, 32400 - 0x90 - outsize);
+      outsize = 32400 - 0x90;
+      memcpy(output + 0x7F00 - 0x200, cpc_hw_pal, 16);
+      for (i = 0; i < 16; i++)
+      {
+        output[0x601 + i*2] = (context->Palette[i].R & 0xf0) | (context->Palette[i].B >> 4);
+        output[0x602 + i*2] = context->Palette[i].G >> 4;
+      }
+    }
+    else
+    {
+      memcpy(output + exec_address - load_address, cpc_scr_simple_loader, sizeof(cpc_scr_simple_loader));
+      output[0xd7d0 - load_address] = cpc_mode;
+      //memcpy(output + 0xd7d1 - load_address, cpc_hw_pal, 16);
+      for (i = 0; i < 16; i++)
+      {
+        output[0xd7d1 - load_address + i] = (context->Palette[i].G / 86) * 9 + (context->Palette[i].R / 86) * 3 + (context->Palette[i].B / 86);
+      }
+    }
     if (!Write_bytes(file, output, outsize))
       File_error = 1;
     fclose(file);
+    if (!overscan)
+    {
+      file = Open_file_write_with_alternate_ext(context, "BAS");
+      if (file != NULL)
+      {
+        byte buffer[128];
+        memset(buffer, 0, sizeof(buffer));
+        buffer[2] = 10;  // basic line number
+        buffer[4] = 0xad; // MODE
+        buffer[5] = ' ';
+        buffer[6] = 0x0e + cpc_mode;
+        buffer[7] = 0x01; // :
+        buffer[8] = 0xa8; // LOAD
+        buffer[9] = '"';
+        for (i = 0; i < 8; i++)
+        {
+          if (context->File_name[i] == '\0' || context->File_name[i] == '.')
+            break;
+          buffer[10+i] = (byte)toupper(context->File_name[i]);
+        }
+        memcpy(buffer + 10 + i, ".SCR\"", 5);
+        i += 15;
+        buffer[i++] = 0x01; // :
+        buffer[i++] = 0x83; // CALL
+        buffer[i++] = 0x1c; // &
+        buffer[i++] = 0xd0;
+        buffer[i++] = 0xc7;
+        buffer[i++] = 0x00;
+        buffer[0] = (byte)i; // length of line data
+        CPC_write_AMSDOS_header(file, context->File_name, "BAS", 0, 0x170, 0, i + 2);
+        if (!Write_bytes(file, buffer, 128))
+          File_error = 1;
+        fclose(file);
+      }
+    }
   }
   free (output);
 }

src/impdraw_loader.h

@@ -0,0 +1,65 @@
+/* vim:expandtab:ts=2 sw=2:
+ */
+/**
+ * Amstrad CPC Loader for overscan picture.
+ * Locomotive BASIC + Z80 Code
+ * (c) Ast/iMP4CT
+ * https://amstradplus.forumforever.com/t462-iMPdraw-v2-0.htm?start=45
+ */
+static const unsigned char impdraw_loader[] = {
+  0x0e, 0x00, 0x0a, 0x00, 0x01, 0xc0, 0x20, 0x69, // starts at &0170
+  0x4d, 0x50, 0x20, 0x76, 0x32, 0x00, 0x0d, 0x00, // 10 ' iMP v2
+  0x14, 0x00, 0xad, 0x20, 0x0e, 0x01, 0x83, 0x1c, // 20 MODE 0:CALL &1ad
+  0xad, 0x01, 0x00, 0x00, 0x00,                   // &0184 : token 0x0e = 0, 0x0f = 1, 0x10 = 2
+  0x01, 0x30, 0x02, 0x32, 0x06, 0x22, 0x07, 0x23, // From &018d CRTC registers
+  0x0c, 0x0d, 0xd0, 0x00, 0x00, 0x3f,
+  0xff, 0x00, 0xff, 0x77, 0xb3, 0x51, 0xa8, 0xd4, // From &019b CPC Plus ASIC unlocking sequence
+  0x62, 0x39, 0x9c, 0x46, 0x2b, 0x15, 0x8a, 0xcd,
+  0xee,
+  0x00,                                           // &01ac = CPC PLUS flag (0=CPC old, 1=CPC+)
+  0xf3,             // 01ad di
+  0x21, 0x8d, 0x01, // 01ae ld hl,&018d
+  0x3e, 0x06,       // 01b1 ld a,&06
+  0x01, 0xbe, 0xbd, // 01b3 ld bc,BDBE
+  0xed, 0xa3,       // 01b6 outi  ; first decrements b  <---+
+  0x41,             // 01b8 ld b,c                          |
+  0xed, 0xa3,       // 01b9 outi                            |
+  0x3d,             // 01bb dec a                           |
+  0x20, 0xf8,       // 01bc jz nz,01B6   ; loop ------------+
+  // load colors into gate array (from 7F00 ;)
+  0x01, 0x00, 0x7f, // 01be ld bc,7F00 ; Gate array
+  0x1e, 0x10,       // 01c1 ld e,10
+  0x0a,             // 01c3 ld a,(bc)               <---+
+  0xed, 0x49,       // 01c4 out (c),c   ; select ink#   |
+  0xed, 0x79,       // 01c6 out (c),a   ; set ink       |
+  0x0c,             // 01c8 inc c                       |
+  0x1d,             // 01c9 dec e                       |
+  0x20, 0xf7,       // 01ca jz nz,01C3  ; loop ---------+
+
+  0x3a, 0xac, 0x01, // 01cc ld a,01AC   ; CPC PLUS flag
+  0xfe, 0x01,       // 01cf cp 01
+  0x20, 0x22,       // 01d1 jz nz,01F5  ; flag != 1 => skip CPC+
+  // CPC Plus ASIC unlock
+  0x21, 0x9b, 0x01, // 01d3 ld hl,019B
+  0x01, 0x11, 0xbc, // 01d6 ld bc,BC11
+  0x7e,             // 01d9 ld a,(hl)       <---+
+  0xed, 0x79,       // 01da out (c),a           |
+  0x2c,             // 01dc inc l               |
+  0x0d,             // 01dd dec c               |
+  0x20, 0xf9,       // 01de jr nz,01D9 ; loop --+
+  // set CPC Plus colors
+  0x01, 0xb8, 0x7f, // 01e0 ld bc,7FB8
+  0xed, 0x49,       // 01e3 out (c),c     ; open ASIC I/O
+  0x21, 0x01, 0x08, // 01e5 ld hl,0801
+  0x11, 0x00, 0x64, // 01e8 ld de,6400
+  0x01, 0x20, 0x00, // 01eb ld bc,0020
+  0xed, 0xb0,       // 01ee ldir          ; copy bc bytes from (hl) to (de)
+  0x01, 0xa0, 0x7f, // 01f0 ld bc,7FA0
+  0xed, 0x49,       // 01f3 out (c),c     ; close ASIC I/O
+
+  0x21, 0xf9, 0xb7, // 01f5 ld hl,B7F9    ; SCR Event Block: Set Inks
+  0xcd, 0xdd, 0xbc, // 01f8 call BCDD     ; remove event block for CRTC IRQ
+  0xfb,             // 01fb ei
+  0xc3, 0x18, 0xbb, // 01fc jp BB18       ; Wait Keypress
+  0x00              // 01ff
+};

src/oldies.c

@@ -27,6 +27,7 @@
 #endif
 #include <stdlib.h>
 #include <stdio.h>
+#include <ctype.h>
 #include <math.h>
 #include "struct.h"
 #include "oldies.h"
@@ -724,6 +725,23 @@ int CPC_compare_colors(T_Components * col1, T_Components * col2)
   return v1 == v2;
 }
 
+int CPC_is_CPC_old_color(T_Components * col)
+{
+  if (15 < col->R && col->R < 0x60)
+    return 0;
+  if (0x82 < col->R && col->R < 0xf0)
+    return 0;
+  if (15 < col->G && col->G < 0x60)
+    return 0;
+  if (0x82 < col->G && col->G < 0xf0)
+    return 0;
+  if (15 < col->B && col->B < 0x60)
+    return 0;
+  if (0x82 < col->B && col->B < 0xf0)
+    return 0;
+  return 1;
+}
+
 void CPC_set_default_BASIC_palette(T_Components * palette)
 {
   static const byte basic_colors[] = {
@@ -808,6 +826,43 @@ int CPC_check_AMSDOS(FILE * file, word * loading_address, word * exec_address, u
   return 1;
 }
 
+int CPC_write_AMSDOS_header(FILE * file, const char * filename, const char * ext, byte type, word load_address, word exec_address, word file_length)
+{
+  int i;
+  word checksum = 0;
+  byte header[128];
+
+  memset(header, 0, sizeof(header));
+  memset(header + 1, ' ', 11);
+  for (i = 0 ; i < 8; i++)
+  {
+    if (filename[i] == '\0' || filename[i] == '.')
+      break;
+    header[1+i] = (byte)toupper(filename[i]);
+  }
+  for (i = 0 ; i < 3; i++)
+  {
+    if (ext[i] == '\0' || ext[i] == '.')
+      break;
+    header[9+i] = (byte)toupper(ext[i]);
+  }
+  header[18] = type;
+  header[21] = load_address & 0xff;
+  header[22] = load_address >> 8;
+  header[24] = file_length & 0xff;
+  header[25] = file_length >> 8;
+  header[26] = exec_address & 0xff;
+  header[27] = exec_address >> 8;
+  header[64] = file_length & 0xff;
+  header[65] = file_length >> 8;
+  for (i = 0; i < 67; i++)
+    checksum += (word)header[i];
+  header[67] = checksum & 0xff;
+  header[68] = checksum >> 8;
+  GFX2_LogHexDump(GFX2_DEBUG, "AMSDOS ", header, 0, sizeof(header));
+  return Write_bytes(file, header, sizeof(header));
+}
+
 int DECB_Check_binary_file(FILE * f)
 {
   byte code;

src/oldies.h

@@ -109,6 +109,11 @@ void ZX_Spectrum_set_palette(T_Components * palette);
  */
 void CPC_set_HW_palette(T_Components * palette);
 
+/**
+ * Check if the color is likely to be a CPC RGB tri level color
+ */
+int CPC_is_CPC_old_color(T_Components * col);
+
 /**
  * Set 16 color default Amstrad CPC BASIC palette
  *
@@ -147,6 +152,11 @@ byte CPC_Firmware_to_Hardware_color(byte fw_color);
  */
 int CPC_check_AMSDOS(FILE * file, word * loading_address, word * exec_address, unsigned long * file_length);
 
+/**
+ * Write AMSDOS header
+ */
+int CPC_write_AMSDOS_header(FILE * file, const char * filename, const char * ext, byte type, word load_address, word save_address, word file_length);
+
 /** @}*/
 
 /** @defgroup decb DECB binary format