Added 0.030 of PicoDrive and moved license files into root

[cyclone68000.git] / Pico / Cart.cpp

diff --git a/Pico/Cart.cpp b/Pico/Cart.cpp
new file mode 100644 (file)
index 0000000..e7b81c1
--- /dev/null
+++ b/Pico/Cart.cpp
@@ -0,0 +1,92 @@
+\r
+#include "PicoInt.h"\r
+\r
+static void Byteswap(unsigned char *data,int len)\r
+{\r
+  int i=0;\r
+\r
+  if (len<2) return; // Too short\r
+\r
+  do\r
+  {\r
+    unsigned short *pd=(unsigned short *)(data+i);\r
+    int value=*pd; // Get 2 bytes\r
+\r
+    value=(value<<8)|(value>>8); // Byteswap it\r
+    *pd=(unsigned short)value; // Put 2b ytes\r
+    i+=2;\r
+  }  \r
+  while (i+2<=len);\r
+}\r
+\r
+// Interleve a 16k block and byteswap\r
+static int InterleveBlock(unsigned char *dest,unsigned char *src)\r
+{\r
+  int i=0;\r
+  for (i=0;i<0x2000;i++) dest[(i<<1)  ]=src[       i]; // Odd\r
+  for (i=0;i<0x2000;i++) dest[(i<<1)+1]=src[0x2000+i]; // Even\r
+  return 0;\r
+}\r
+\r
+// Decode a SMD file\r
+static int DecodeSmd(unsigned char *data,int len)\r
+{\r
+  unsigned char *temp=NULL;\r
+  int i=0;\r
+\r
+  temp=(unsigned char *)malloc(0x4000);\r
+  if (temp==NULL) return 1;\r
+  memset(temp,0,0x4000);\r
+\r
+  // Interleve each 16k block and shift down by 0x200:\r
+  for (i=0; i+0x4200<=len; i+=0x4000)\r
+  {\r
+    InterleveBlock(temp,data+0x200+i); // Interleve 16k to temporary buffer\r
+    memcpy(data+i,temp,0x4000); // Copy back in\r
+  }\r
+\r
+  free(temp);\r
+  return 0;\r
+}\r
+\r
+int PicoCartLoad(FILE *f,unsigned char **prom,unsigned int *psize)\r
+{\r
+  unsigned char *rom=NULL; int size=0;\r
+  if (f==NULL) return 1;\r
+\r
+  fseek(f,0,SEEK_END); size=ftell(f); fseek(f,0,SEEK_SET);\r
+\r
+  size=(size+3)&~3; // Round up to a multiple of 4\r
+\r
+  // Allocate space for the rom plus padding\r
+  rom=(unsigned char *)malloc(size+4);\r
+  if (rom==NULL) { fclose(f); return 1; }\r
+  memset(rom,0,size+4);\r
+\r
+  fread(rom,1,size,f); // Load up the rom\r
+  fclose(f);\r
+\r
+  // Check for SMD:\r
+  if ((size&0x3fff)==0x200) { DecodeSmd(rom,size); size-=0x200; } // Decode and byteswap SMD\r
+  else Byteswap(rom,size); // Just byteswap\r
+  \r
+  if (prom)  *prom=rom;\r
+  if (psize) *psize=size;\r
+\r
+  return 0;\r
+}\r
+\r
+// Insert/remove a cartridge:\r
+int PicoCartInsert(unsigned char *rom,unsigned int romsize)\r
+{\r
+  // Make sure movie playing/recording is stopped:\r
+  if (PmovFile) fclose(PmovFile);\r
+  PmovFile=NULL; PmovAction=0;\r
+\r
+  memset(&Pico,0,sizeof(Pico)); // Blank Pico state\r
+  Pico.rom=rom;\r
+  Pico.romsize=romsize;\r
+  PicoReset();\r
+\r
+  return 0;\r
+}\r