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authorIan C <ianc@noddybox.co.uk>2016-12-16 16:49:34 +0000
committerIan C <ianc@noddybox.co.uk>2016-12-16 16:49:34 +0000
commit3b86882357e8e02fc2740f16780d1c4620ea0c57 (patch)
treef1197d92e3472c71ff9a9a80dfdb49ebaed569ea /src/cpcout.c
parent0127dbc7c79ba19c21ef07f2b1764857f5bf9717 (diff)
Added initial files for CPC output.
Diffstat (limited to 'src/cpcout.c')
-rw-r--r--src/cpcout.c274
1 files changed, 274 insertions, 0 deletions
diff --git a/src/cpcout.c b/src/cpcout.c
new file mode 100644
index 0000000..6dbafc1
--- /dev/null
+++ b/src/cpcout.c
@@ -0,0 +1,274 @@
+/*
+
+ casm - Simple, portable assembler
+
+ Copyright (C) 2003-2015 Ian Cowburn (ianc@noddybox.co.uk)
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see <http://www.gnu.org/licenses/>.
+
+ -------------------------------------------------------------------------
+
+ Commodore CPC tape output handler.
+
+*/
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+
+#include "global.h"
+#include "codepage.h"
+#include "cpcout.h"
+#include "expr.h"
+
+
+/* ---------------------------------------- MACROS & TYPES
+*/
+
+enum option_t
+{
+ OPT_START_ADDR,
+};
+
+static const ValueTable option_set[] =
+{
+ {"cpc-start", OPT_START_ADDR},
+ {NULL}
+};
+
+typedef struct
+{
+ int start_addr;
+} Options;
+
+static Options options = {-1};
+
+/* ---------------------------------------- PRIVATE FUNCTIONS
+*/
+
+static int PokeB(Byte *mem, int addr, Byte b)
+{
+ mem[addr++] = b;
+ return (addr % 0x10000);
+}
+
+
+static int PokeW(Byte *mem, int addr, int w)
+{
+ addr = PokeB(mem, addr, w & 0xff);
+ return PokeB(mem, addr, (w & 0xff00) >> 8);
+}
+
+
+static int PokeS(Byte *mem, int addr, const char *str)
+{
+ while(*str)
+ {
+ addr = PokeB(mem, addr, CodeFromNative(CP_ASCII, *str++));
+ }
+
+ return addr;
+}
+
+
+static void WriteByte(FILE *fp, Byte b)
+{
+ putc(b, fp);
+}
+
+
+static void WriteWord(FILE *fp, int w)
+{
+ WriteByte(fp, w & 0xff);
+ WriteByte(fp, (w & 0xff00) >> 8);
+}
+
+
+static void WriteLong(FILE *fp, unsigned long l)
+{
+ int f;
+
+ for(f = 0; f < 4; f++)
+ {
+ WriteByte(fp, l & 0xff);
+ l >>= 8u;
+ }
+}
+
+
+static void WriteString(FILE *fp, const char *p, int len,
+ Byte fill, Codepage cp)
+{
+ while(len--)
+ {
+ WriteByte(fp, *p ? CodeFromNative(cp, *p++) : CodeFromNative(cp, fill));
+ }
+}
+
+
+/* ---------------------------------------- INTERFACES
+*/
+const ValueTable *CPCOutputOptions(void)
+{
+ return option_set;
+}
+
+CommandStatus CPCOutputSetOption(int opt, int argc, char *argv[], int quoted[],
+ char *err, size_t errsize)
+{
+ CommandStatus stat = CMD_OK;
+
+ CMD_ARGC_CHECK(1);
+
+ switch(opt)
+ {
+ case OPT_START_ADDR:
+ CMD_EXPR(argv[0], options.start_addr);
+ break;
+
+ default:
+ break;
+ }
+
+ return stat;
+}
+
+int CPCOutput(const char *filename, const char *filename_bank,
+ MemoryBank **bank, int count, char *error, size_t error_size)
+{
+ FILE *fp = fopen(filename, "wb");
+ int f;
+ int offset;
+
+ if (!fp)
+ {
+ snprintf(error, error_size, "Failed to create %s", filename);
+ return FALSE;
+ }
+
+ /* Write signature
+ */
+ WriteString(fp, "C64 tape image file", 32, 0, CP_ASCII);
+
+ /* Write directory header
+ */
+ WriteWord(fp, 0x200);
+ WriteWord(fp, count);
+ WriteWord(fp, count);
+ WriteString(fp, filename, 24, ' ', CP_ASCII);
+
+ /* Offset to tape data
+ */
+ offset = 64 + 32 * count;
+
+ /* Write directory entries
+ */
+ for(f = 0; f < count; f++)
+ {
+ int min, max, len;
+
+ min = bank[f]->min_address_used;
+ max = bank[f]->max_address_used;
+
+ /* If this is the first bank, we're going to prepend some BASIC
+ */
+ if (f == 0)
+ {
+ if (min < 0x810)
+ {
+ snprintf(error, error_size, "First bank starts below a safe "
+ "area to add BASIC loader");
+
+ return FALSE;
+ }
+
+ min = 0x801; /* Start of BASIC */
+ }
+
+ len = max - min + 1;
+
+ WriteByte(fp, 1);
+ WriteByte(fp, 0x82);
+ WriteWord(fp, min);
+ WriteWord(fp, max + 1);
+ WriteLong(fp, offset);
+
+ if (count == 1)
+ {
+ WriteString(fp, filename, 16, ' ', CP_CBM);
+ }
+ else
+ {
+ char fn[16];
+
+ snprintf(fn, sizeof fn, filename_bank, bank[f]->number);
+ WriteString(fp, fn, 16, ' ', CP_CBM);
+ }
+
+ /* +2 is to include the 2-byte PRG header
+ offset += len + 2;
+ */
+ offset += len;
+ }
+
+ /* Write actual contents
+ */
+ for(f = 0; f < count; f++)
+ {
+ Byte *mem;
+ int min, max, len;
+
+ mem = bank[f]->memory;
+
+ min = bank[f]->min_address_used;
+ max = bank[f]->max_address_used;
+
+ /* If this is the first bank, we're going to prepend some BASIC.
+ Note that output drivers are allowed to manipulate memory directly.
+ */
+ if (f == 0)
+ {
+ char sys[16];
+ int a = 0x803;
+ int next;
+
+ snprintf(sys, sizeof sys, "%u", min);
+
+ a = PokeW(mem, a, 10);
+ a = PokeB(mem, a, 0x9e);
+ a = PokeS(mem, a, sys);
+ a = PokeB(mem, a, 0x00);
+
+ next = a;
+
+ a = PokeW(mem, a, 0x00);
+
+ PokeW(mem, 0x801, next);
+
+ min = 0x801;
+ }
+
+ len = max - min + 1;
+
+ fwrite(mem + min, len, 1, fp);
+ }
+
+ fclose(fp);
+
+ return TRUE;
+}
+
+
+/*
+vim: ai sw=4 ts=8 expandtab
+*/