tool for converting PDOS basic files to .prg

tools/pdos2prg.js

@@ -0,0 +1,67 @@
+const fs = require('fs');
+const parseOptions = require("./parseOptions");
+
+const options = parseOptions([
+   { name: 'input', alias: 'i', type: String }      
+]);
+
+if(options.input === undefined) {
+   console.log("usage: pdos2prg -i inputfile#[...] ");
+   process.exit(-1);
+}
+
+let s = options.input.split("#");
+if(s.length != 2) {
+   console.log("pdos2prg: filename must contain # tag");
+   process.exit(-1);
+}
+
+let tag = s[1];
+let start_address = tag.substr(2);
+let file_type = tag.substr(0,2).toUpperCase();
+
+let ext = (function(){
+        if(file_type == "F1") return `_BAS_${start_address}`;
+   else if(file_type == "F8") return `_ASOFT_${start_address}`;
+   else                       return `_BIN_${start_address}`;
+})();
+
+let filename = `${s[0]}${ext}.prg`;
+
+start_address = parseInt(start_address,16);
+
+let bin = fs.readFileSync(options.input);
+
+if(file_type == "F1") {
+   bin = bas2bin(bin, start_address);
+   start_address = 0x0002;
+}
+
+let lo = (start_address >> 0) & 0xFF;
+let hi = (start_address >> 8) & 0xFF;
+
+let prg = new Uint8Array([ lo, hi, ...bin ]);
+
+fs.writeFileSync(filename, prg);
+
+console.log(`${filename} written`);
+
+
+// converts pdos integer basic program
+//
+// pdos: $0000-$0049 junk
+//       $004A-$01FF pointers
+//       $0200-end   basic program to relocate at start address
+//
+// returns:
+//       $004A-$01FF   pointers
+//       $0200-start-1 filler
+//       start - end   basic program
+
+function bas2bin(data, addr) {
+   let pointers = data.slice(0x0002, 0x0200);
+   let prg = data.slice(0x0200);
+   let diff = new Array(addr - 0x0200).fill(0);
+   let joined = [ ...pointers, ...diff, ...prg];
+   return joined;
+}