//
-// 6502 Assembler
+// RMAC - Reboot's Macro Assembler for all Atari computers
+// 6502.C - 6502 Assembler
+// Copyright (C) 199x Landon Dyer, 2011-2017 Reboot and Friends
+// RMAC derived from MADMAC v1.07 Written by Landon Dyer, 1986
+// Source utilised with the kind permission of Landon Dyer
//
// Init6502 initialization
// d_6502 handle ".6502" directive
// Exported vars
const char in_6502mode[] = "directive illegal in .6502 section";
uint16_t * currentorg = &orgmap[0][0]; // Current org range
+char strtoa8[128]; // ASCII to Atari 800 internal conversion table
//
// 6502 addressing modes;
-1 // ZPY
};
+static char a8internal[] =
+{
+ ' ', 0, '!', 1, '"', 2, '#', 3, '$', 4, '%', 5, '&', 6, '\'', 7,
+ '(', 8, ')', 9, '*', 10, '+', 11, ',', 12, '-', 13, '.', 14, '/', 15,
+ '0', 16, '1', 17, '2', 18, '3', 19, '4', 20, '5', 21, '6', 22, '7', 23,
+ '8', 24, '9', 25, ':', 26, ';', 27, '<', 28, '=', 29, '>', 30, '?', 31,
+ '@', 32, 'A', 33, 'B', 34, 'C', 35, 'D', 36, 'E', 37, 'F', 38, 'G', 39,
+ 'H', 40, 'I', 41, 'J', 42, 'K', 43, 'L', 44, 'M', 45, 'N', 46, 'O', 47,
+ 'P', 48, 'Q', 49, 'R', 50, 'S', 51, 'T', 52, 'U', 53, 'V', 54, 'W', 55,
+ 'X', 56, 'Y', 57, 'Z', 58, '[', 59, '\\', 60, ']', 61, '^', 62, '_', 63,
+ 'a', 97, 'b', 98, 'c', 99, 'd', 100, 'e', 101, 'f', 102, 'g', 103, 'h', 104,
+ 'i', 105, 'j', 106, 'k', 107, 'l', 108, 'm', 109, 'n', 110, 'o', 111, 'p', 112,
+ 'q', 113, 'r', 114, 's', 115, 't', 116, 'u', 117, 'v', 118, 'w', 119, 'x', 120,
+ 'y', 121, 'z', 122
+};
+
//
// Initialize 6502 assembler
// Set up first org section (set to zero)
orgmap[0][0] = 0;
+
+ SwitchSection(M6502); // Switch to 6502 section
+
+ // Initialise string conversion table(s)
+ char * p = a8internal;
+ memset(strtoa8, 31, 128); // 31=fallback value ("?")
+
+ for(; p<a8internal+sizeof(a8internal); p+=2)
+ strtoa8[p[0]] = p[1];
+
+ if (challoc == 0)
+ {
+ // Allocate and clear 64K of space for the 6502 section
+ chcheck(UPSEG_SIZE);
+ memset(sect[M6502].scode->chptr, 0, UPSEG_SIZE);
+ }
+
+ SwitchSection(TEXT); // Go back to TEXT
}
SaveSection(); // Save curent section
SwitchSection(M6502); // Switch to 6502 section
- if (challoc == 0)
- {
- // Allocate and clear 64K of space for the 6502 section
- chcheck(UPSEG_SIZE);
- memset(sect[M6502].scode->chptr, 0, UPSEG_SIZE);
- }
-
return 0;
}
{
register int amode; // (Parsed) addressing mode
register int i;
- VALUE eval; // Expression value
+ uint64_t eval; // Expression value
WORD eattr; // Expression attributes
int zpreq; // 1, optimize instr to zero-page form
register char * p; // (Temp) string usage
//
zpreq = 0;
- switch ((int)*tok)
+ switch (tok.u32[0])
{
case EOL:
amode = A65_IMPL;
break;
case '#':
- tok++;
+ tok.u32++;
- if (*tok == '>')
+ if (*tok.u32 == '>')
{
- tok++;
+ tok.u32++;
+
if (expr(exprbuf, &eval, &eattr, NULL) < 0)
return;
amode = A65_IMMEDH;
break;
}
- else if (*tok == '<')
+ else if (*tok.u32 == '<')
{
- tok++;
+ tok.u32++;
+
if (expr(exprbuf, &eval, &eattr, NULL) < 0)
return;
break;
case '(':
- tok++;
+ tok.u32++;
if (expr(exprbuf, &eval, &eattr, NULL) < 0)
return;
- if (*tok == ')')
+ if (*tok.u32 == ')')
{
// (foo) or (foo),y
- if (*++tok == ',')
+ if (*++tok.u32 == ',')
{
// (foo),y
- tok++;
- p = string[tok[1]];
+ tok.u32++;
+ p = string[tok.u32[1]];
- if (*tok != SYMBOL || p[1] != EOS || (*p | 0x20) != 'y') // Sleazo tolower()
+ // Sleazo tolower() ---------------------vvvvvvvvvvv
+ if (*tok.u32 != SYMBOL || p[1] != EOS || (*p | 0x20) != 'y')
goto badmode;
- tok += 2;
+ tok.u32 += 2;
amode = A65_INDY;
}
else
amode = A65_IND;
}
- else if (*tok == ',')
+ else if (*tok.u32 == ',')
{
// (foo,x)
- tok++;
- p = string[tok[1]];
+ tok.u32++;
+ p = string[tok.u32[1]];
- if (*tok != SYMBOL || p[1] != EOS || (*p | 0x20) != 'x') // Sleazo tolower()
+ // Sleazo tolower() ---------------------vvvvvvvvvvv
+ if (*tok.u32 != SYMBOL || p[1] != EOS || (*p | 0x20) != 'x')
goto badmode;
- tok += 2;
+ tok.u32 += 2;
- if (*tok++ != ')')
+ if (*tok.u32++ != ')')
goto badmode;
amode = A65_INDX;
break;
case '@':
- tok++;
+ tok.u32++;
if (expr(exprbuf, &eval, &eattr, NULL) < 0)
return;
- if (*tok == '(')
+ if (*tok.u32 == '(')
{
- tok++;
- p = string[tok[1]];
+ tok.u32++;
+ p = string[tok.u32[1]];
- if (*tok != SYMBOL || p[1] != EOS || tok[2] != ')' || tok[3] != EOL)
+ if (*tok.u32 != SYMBOL || p[1] != EOS || tok.u32[2] != ')' || tok.u32[3] != EOL)
goto badmode;
i = (*p | 0x20); // Sleazo tolower()
else
goto badmode;
- tok += 3; // Past SYMBOL <string> ')' EOL
+ tok.u32 += 3; // Past SYMBOL <string> ')' EOL
zpreq = 1; // Request zeropage optimization
}
- else if (*tok == EOL)
+ else if (*tok.u32 == EOL)
amode = A65_IND;
else
goto badmode;
// x,foo
// y,foo
//
- p = string[tok[1]];
+ p = string[tok.u32[1]];
// ggn: the following code is effectively disabled as it would make
// single letter labels not work correctly (would not identify the
// label properly). And from what I understand it's something to
zpreq = 1;
- if (*tok == EOL)
+ if (*tok.u32 == EOL)
amode = A65_ABS;
- else if (*tok == ',')
+ else if (*tok.u32 == ',')
{
- tok++;
- p = string[tok[1]];
+ tok.u32++;
+ p = string[tok.u32[1]];
- if (*tok != SYMBOL || p[1] != EOS)
+ if (*tok.u32 != SYMBOL || p[1] != EOS)
goto badmode;
- tok += 2;
+ tok.u32 += 2;
//
// Check for X or Y index register;
if (sloc > 0x10000L)
fatal("6502 code pointer > 64K");
- if (*tok != EOL)
+ if (*tok.u32 != EOL)
error(extra_stuff);
}
// Generate 6502 object output file.
//
// ggn: converted into a com/exe/xex output format
-// Notes: 1. The $FFFF is only mandatory for the first segment, but let's
-// dump it everywhere for now
-// 2. It's still dumping pages instead of more fine grained stuff.
-// Should look into this - a8 people don't like waste so much ;)
void m6502obj(int ofd)
{
uint16_t exeheader[3];
projects / rmac / blobdiff