Made EquiRAM structure the main source of truth about sizing

equi.c

@@ -28,16 +28,20 @@
 #else
 
 #define cgetc() (fgetc(stdin))
+#define cputc(c) (fputc(c, stdout))
 
 #endif
 
 /* Definitions section */
 
+#define EQUI_VER "0.0.1"
+
 #define ushort unsigned short /* basic 16-bit integer */
 #define uchar unsigned char /* basic 8-bit integer */
 #define WS sizeof(ushort) /* Equi word size in bytes */
 #define CLT_ENTRY_LEN 6u /* Amount of significant compiled word characters */
 #define CLT_ENTRY_SIZE (CLT_ENTRY_LEN + WS) /* Full size in bytes taken by one CLT entry */
+#define BS 8u /* Backspace character code */
 
 /* Configuration section (constants overridable at compile-time) */
 
@@ -51,14 +55,9 @@
 #define LIT_STACK_SIZE 32u
 #endif
 
-/* GPD (general purpose data) area start address */
-#ifndef GPD_AREA_START
-#define GPD_AREA_START 0x2300u
-#endif
-
-/* Command buffer start address */
-#ifndef CMD_BUF_START
-#define CMD_BUF_START 0x3b80u
+/* Command buffer size in bytes */
+#ifndef GPD_AREA_SIZE
+#define GPD_AREA_SIZE 6400u
 #endif
 
 /* Command buffer size in bytes */
@@ -66,33 +65,18 @@
 #define CMD_BUF_SIZE 15600u
 #endif
 
+/* Maximum amount of CLT entries */
+#ifndef CLT_ENTRIES_MAX
+#define CLT_ENTRIES_MAX 512u
+#endif
+
 /* Some necessary constants and offsets derived from the above values */
 #define STACK_SIZE_WORDS (STACK_SIZE / WS) /* Main and return stack size in words */
-#define MAIN_STACK_ADDR 0u /* Main stack address */
-#define RETURN_STACK_ADDR STACK_SIZE /* Return stack address */
-#define LIT_STACK_ADDR (RETURN_STACK_ADDR + STACK_SIZE) /* Literal stack address */
-#define PC_ADDR (LIT_STACK_ADDR + LIT_STACK_SIZE) /* Program counter address */
-#define CBP_ADDR (PC_ADDR + WS) /* Compilation buffer pointer location address */
-#define CLTP_ADDR (CBP_ADDR + WS) /* Compilation lookup table pointer location address */
-#define FLAGS_ADDR (CLTP_ADDR + WS) /* Flags register address */
-#define GPD_START_LOC_ADDR (FLAGS_ADDR + 1u) /* Location where GPD_AREA_START value is stored */
-#define CMD_START_LOC_ADDR (GPD_START_LOC_ADDR + WS) /* Location where CMD_BUF_START value is stored */
-#define CMD_SIZE_LOC_ADDR (CMD_START_LOC_ADDR + WS) /* Location where CMD_BUF_SIZE value is stored */
-#define CLT_START (CMD_SIZE_LOC_ADDR + 213u) /* should be 0x300 by default */
-#define CLT_SIZE (GPD_AREA_START - CLT_START) /* Compilation lookup table size in bytes */
-#define CLT_ENTRIES_MAX (CLT_SIZE / CLT_ENTRY_SIZE) /* Maximum amount of entries in CLT, must be integer */
-#define GPD_AREA_SIZE (CMD_BUF_START - GPD_AREA_START) /* GPD area size in bytes */
 
 /*
  * Structures that describe Equi machine RAM using the above configuration
  */
 
-struct EquiFlags {
-  unsigned int II:1; /* instruction ignore mode */
-  unsigned int CM:1; /* compilation mode */
-  unsigned int IM:1; /* interpretation mode */
-};
-
 struct CLTEntry {
   uchar name[CLT_ENTRY_LEN]; /* compiled word name */
   ushort loc;    /* compiled word location */
@@ -108,17 +92,18 @@ struct EquiRAM {
   uchar lsp; /* literal stack pointer */
   ushort cbp; /* compilation buffer pointer */
   ushort cltp; /* compilation lookup table pointer */
-  struct EquiFlags flags;
+  unsigned int II:1; /* instruction ignore mode */
+  unsigned int CM:1; /* compilation mode */
+  unsigned int IM:1; /* interpretation mode */
   ushort gpd_start;
   ushort cmd_start;
   ushort cmd_size;
-  uchar reserved[206u]; /* reserved space */
+  ushort ibp; /* input buffer pointer */
   struct CLTEntry clt[CLT_ENTRIES_MAX]; /* compilation lookup table */
   uchar gpd[GPD_AREA_SIZE];
   uchar cmdbuf[CMD_BUF_SIZE];
 };
 
-
 /* Before running the main code, instantiate the machine RAM */
 static struct EquiRAM ram;
 
@@ -127,12 +112,20 @@ static uchar* flatram = (uchar *)&ram;
 
 int main(int argc, char* argv[]) {
   /* initialize the RAM in the most standard way */
-  ram.gpd_start = GPD_AREA_START;
-  ram.cmd_start = CMD_BUF_START;
+  ram.gpd_start = (uchar *)&ram.gpd - (uchar *)&ram.main_stack;
+  ram.cmd_start = (uchar *)&ram.cmdbuf - (uchar *)&ram.main_stack;
   ram.cmd_size = CMD_BUF_SIZE;
+  ram.pc = ram.cmd_start; /* Start execution from the start of command buffer */
+  ram.ibp = ram.cmd_start; /* Start input buffering from the start of command buffer */
 
-  printf("Equi command buffer: 0x%X\n", ram.cmd_size);
+  printf("Welcome to Equi v" EQUI_VER " by Luxferre, 2022\n\nCLT: 0x%X (%d bytes)\nGPD: 0x%X (%d bytes)\nCommand buffer: 0x%X (%d bytes)\nEqui ready\n\n",
+      (uchar *)&ram.clt - (uchar *)&ram.main_stack,
+      (uchar *)&ram.gpd - (uchar *)&ram.clt,
+      ram.gpd_start,
+      ram.cmd_start - ram.gpd_start,
+      ram.cmd_start, ram.cmd_size);
 
+  cputc('>');
   cgetc();