Preliminary BBC Micro support

.gitignore

@@ -27,5 +27,7 @@ src/test/scala/experiments/
 *.a78
 *.a2
 *.dsk
+*.inf
+HELLO
 
 

docs/api/target-platforms.md

@@ -35,6 +35,8 @@ Read [the NES programming guide](./famicom-programming-guide.md) for more info.
 
 * `a8` – Atari 8-bit computers
 
+* `bbcmicro` – BBC Micro model B (32k RAM)
+
 * `apple2` – Apple II+/IIe/Enhanced IIe
 
 The primary and most tested platform is Commodore 64.
@@ -59,6 +61,20 @@ The file has to be loaded from $0C00. An example how to put such file onto a dis
     
 Creating a bootable disk is beyond the scope of this document.
 
+### A note about BBC Micro
+
+The default configuration file puts the start address for the program at $0E00.
+
+The compiler outputs two files: a raw machine code file without an extension and a `.inf` file with file metadata.
+To use the file, you need to put it on a disk or a disk image.
+You can for example use tools like BBC Disk Explorer.
+
+After putting it on a disk, the file can be run with:
+
+    *RUN "FILENAME"
+    
+Currently, multipart BBC Micro programs are not supported.
+
 ## Adding a custom platform
 
 Every platform is defined in an `.ini` file with an appropriate name.

include/bbc_hardware.mfk

@@ -0,0 +1 @@
+

include/bbc_kernal.mfk

@@ -0,0 +1,4 @@
+
+// OSASCI. Write a character (to screen) from A plus LF if (A)=&0D
+// Input: A = Byte to write.
+asm void putchar(byte a) @$FFE3 extern

include/bbcmicro.ini

@@ -0,0 +1,21 @@
+[compilation]
+; "strict" guarantees compatibility with Rockwell CPU's in some later Model B's
+arch=strict
+modules=bbc_kernal,bbc_hardware,default_panic
+
+
+[allocation]
+; TODO
+zp_pointers=$70, $72, $74, $76, $78, $7A, $7C, $7E, $80, $82, $84, $86, $88, $8A, $8C, $8E
+; $0E00 increases chances it will work on Electrons
+segment_default_start=$0E00
+; The following is for Model B; for Model A, consider changing it to $31FF
+segment_default_end=$71FF
+
+[output]
+style=single
+format=allocated
+extension=
+bbc_inf=true
+
+

src/main/scala/millfork/Main.scala

@@ -166,6 +166,12 @@ object Main {
     c.runFileName.foreach(program =>
       new ProcessBuilder(program, Paths.get(defaultPrgOutput).toAbsolutePath.toString).start()
     )
+    if (platform.generateBbcMicroInfFile) {
+      val start = platform.codeAllocators("default").startAt
+      val codeLength = result.code("default").length
+      Files.write(Paths.get(defaultPrgOutput+".inf"),
+        s"$defaultPrgOutput ${start.toHexString} ${start.toHexString} ${codeLength.toHexString}".getBytes(StandardCharsets.UTF_8))
+    }
   }
 
   private def parser = new CliParser[Context] {

src/main/scala/millfork/Platform.scala

@@ -24,6 +24,7 @@ class Platform(
                 val codeAllocators: Map[String, UpwardByteAllocator],
                 val variableAllocators: Map[String, VariableAllocator],
                 val fileExtension: String,
+                val generateBbcMicroInfFile: Boolean,
                 val bankNumbers: Map[String, Int],
                 val defaultCodeBank: String,
                 val outputStyle: OutputStyle.Value
@@ -157,6 +158,7 @@ object Platform {
       }
     }.toList)
     val fileExtension = os.get(classOf[String], "extension", ".bin")
+    val generateBbcMicroInfFile = os.get(classOf[Boolean], "bbc_inf", false)
     val outputStyle = os.get(classOf[String], "style", "single") match {
       case "" | "single" => OutputStyle.Single
       case "per_bank" | "per_segment" => OutputStyle.PerBank
@@ -166,7 +168,8 @@ object Platform {
     new Platform(cpu, flagOverrides, startingModules, outputPackager,
       codeAllocators.toMap,
       variableAllocators.toMap,
-      if (fileExtension.startsWith(".")) fileExtension else "." + fileExtension,
+      if (fileExtension == "" || fileExtension.startsWith(".")) fileExtension else "." + fileExtension,
+      generateBbcMicroInfFile,
       bankNumbers,
       defaultCodeBank,
       outputStyle)

src/test/scala/millfork/test/emu/EmuPlatform.scala

@@ -15,6 +15,7 @@ object EmuPlatform {
     Map("default" -> new UpwardByteAllocator(0x200, 0xb000)),
     Map("default" -> new VariableAllocator((0 until 256 by 2).toList, new AfterCodeByteAllocator(0xff00))),
     ".bin",
+    false,
     Map("default" -> 0),
     "default",
     OutputStyle.Single