zasm emul: bring back kernel/user distinction

It was a bad idea to remove it. Now that I'm introducing the concept of
a per-app glue file, it becomes much easier to build emulated zasm as a
userspace app.

.gitignore

@@ -0,0 +1 @@
+/kernel/user.h

apps/zasm/glue.asm

@@ -0,0 +1,62 @@
+; zasm
+;
+; Reads input from specified blkdev ID, assemble the binary in two passes and
+; spit the result in another specified blkdev ID.
+;
+; We don't buffer the whole source in memory, so we need our input blkdev to
+; support Seek so we can read the file a second time. So, for input, we need
+; GetC and Seek.
+;
+; For output, we only need PutC. Output doesn't start until the second pass.
+;
+; The goal of the second pass is to assign values to all symbols so that we
+; can have forward references (instructions referencing a label that happens
+; later).
+;
+; Labels and constants are both treated the same way, that is, they can be
+; forward-referenced in instructions. ".equ" directives, however, are evaluated
+; during the first pass so forward references are not allowed.
+;
+; *** Requirements ***
+; blockdev
+; strncmp
+; addDE
+; addHL
+; upcase
+; unsetZ
+; intoDE
+; intoHL
+; writeHLinDE
+; findchar
+; parseHex
+; parseHexPair
+; blkSel
+; fsFindFN
+; fsOpen
+; fsGetC
+; fsSeek
+; fsTell
+; FS_HANDLE_SIZE
+
+; *** Variables ***
+
+#include "user.h"
+.org	USER_CODE
+
+jp	zasmMain
+
+#include "zasm/util.asm"
+.equ	IO_RAMSTART	USER_RAMSTART
+#include "zasm/io.asm"
+.equ	TOK_RAMSTART	IO_RAMEND
+#include "zasm/tok.asm"
+#include "zasm/parse.asm"
+#include "zasm/expr.asm"
+#include "zasm/instr.asm"
+.equ	DIREC_RAMSTART	TOK_RAMEND
+#include "zasm/directive.asm"
+.equ	SYM_RAMSTART	DIREC_RAMEND
+#include "zasm/symbol.asm"
+.equ	ZASM_RAMSTART	SYM_RAMEND
+#include "zasm/main.asm"
+

apps/zasm/main.asm

@@ -1,44 +1,3 @@
-; zasm
-;
-; Reads input from specified blkdev ID, assemble the binary in two passes and
-; spit the result in another specified blkdev ID.
-;
-; We don't buffer the whole source in memory, so we need our input blkdev to
-; support Seek so we can read the file a second time. So, for input, we need
-; GetC and Seek.
-;
-; For output, we only need PutC. Output doesn't start until the second pass.
-;
-; The goal of the second pass is to assign values to all symbols so that we
-; can have forward references (instructions referencing a label that happens
-; later).
-;
-; Labels and constants are both treated the same way, that is, they can be
-; forward-referenced in instructions. ".equ" directives, however, are evaluated
-; during the first pass so forward references are not allowed.
-;
-; *** Requirements ***
-; blockdev
-; strncmp
-; addDE
-; addHL
-; upcase
-; unsetZ
-; intoDE
-; intoHL
-; writeHLinDE
-; findchar
-; parseHex
-; parseHexPair
-; blkSel
-; fsFindFN
-; fsOpen
-; fsGetC
-; fsSeek
-; fsTell
-; ZASM_RAMSTART	(where we put our variables in RAM)
-; FS_HANDLE_SIZE
-
 ; *** Variables ***
 
 ; A bool flag indicating that we're on first pass. When we are, we don't care
@@ -54,19 +13,6 @@
 .equ	ZASM_CTX_PC		ZASM_LOCAL_PASS+1
 .equ	ZASM_RAMEND		ZASM_CTX_PC+2
 
-#include "zasm/util.asm"
-.equ	IO_RAMSTART	ZASM_RAMEND
-#include "zasm/io.asm"
-.equ	TOK_RAMSTART	IO_RAMEND
-#include "zasm/tok.asm"
-#include "zasm/parse.asm"
-#include "zasm/expr.asm"
-#include "zasm/instr.asm"
-.equ	DIREC_RAMSTART	TOK_RAMEND
-#include "zasm/directive.asm"
-.equ	SYM_RAMSTART	DIREC_RAMEND
-#include "zasm/symbol.asm"
-
 ; Read file through blockdev ID in H and outputs its upcodes through blockdev
 ; ID in L.
 zasmMain:

kernel/user.h.example

@@ -0,0 +1,7 @@
+; Example include file for userspace program
+; All userspace programs include this file in they main source file so that
+; they know a couple of vital things about the system such as where user memory
+; starts. This is an example file with required constants.
+
+.equ    USER_CODE       0x4800  ; Where in memory user code is loaded
+.equ    USER_RAMSTART   0x8800  ; Where in memory user memory begins

tools/emul/Makefile

@@ -11,14 +11,19 @@ all: $(TARGETS)
 shell/kernel.h: shell/shell_.asm
 zasm/kernel.h: zasm/glue.asm
 $(KERNEL_HEADERS):
-	scas -o - -I $(KERNEL) -I $(APPS) $< | ./bin2c.sh KERNEL | tee $@ > /dev/null
+	scas -o - -I $(KERNEL) $< | ./bin2c.sh KERNEL | tee $@ > /dev/null
+
+zasm/user.h: $(APPS)/zasm/glue.asm
+$(USER_HEADERS):
+	scas -o - -I $(APPS) $< | ./bin2c.sh USERSPACE | tee $@ > /dev/null
 
 zasm/includes.cfs: $(CFSPACK)
 	rm -rf zasm/includes
 	cp -r $(KERNEL) zasm/includes
 	cp -r $(APPS)/zasm zasm/includes/zasm
-	find zasm/includes -name *.md -delete
+	find zasm/includes -name *.md -o -name *.example -delete
 	find zasm/includes -type f -exec sed -i -e 's/;.*//g' {} \;
+	cp user.h zasm/includes
 	$(CFSPACK) zasm/includes > $@
 	rm -rf zasm/includes
 
@@ -26,7 +31,7 @@ zasm/includes.h: zasm/includes.cfs
 	./bin2c.sh FSDEV < $< | tee $@ > /dev/null
 	
 shell/shell: shell/shell.c libz80/libz80.o shell/kernel.h $(CFSPACK)
-zasm/zasm: zasm/zasm.c libz80/libz80.o zasm/kernel.h zasm/includes.h
+zasm/zasm: zasm/zasm.c libz80/libz80.o zasm/kernel.h zasm/user.h zasm/includes.h
 runbin/runbin: runbin/runbin.c libz80/libz80.o
 $(TARGETS):
 	cc $< libz80/libz80.o -o $@

tools/emul/user.h

@@ -0,0 +1,22 @@
+.equ    USER_CODE       0x4800
+.equ    USER_RAMSTART   0x5800
+.equ    FS_HANDLE_SIZE  8
+
+; *** JUMP TABLE ***
+.equ    strncmp        0x03
+.equ    addDE          0x06
+.equ    addHL          0x09
+.equ    upcase         0x0c
+.equ    unsetZ         0x0f
+.equ    intoDE         0x12
+.equ    intoHL         0x15
+.equ    writeHLinDE    0x18
+.equ    findchar       0x1b
+.equ    parseHex       0x1e
+.equ    parseHexPair   0x21
+.equ    blkSel         0x24
+.equ    fsFindFN       0x27
+.equ    fsOpen         0x2a
+.equ    fsGetC         0x2d
+.equ    fsSeek         0x30
+.equ    fsTell         0x33

tools/emul/zasm/glue.asm

@@ -6,7 +6,25 @@
 .equ FS_SEEK_PORT	0x03
 .equ STDERR_PORT	0x04
 
-jp	init
+jp     init    ; 3 bytes
+; *** JUMP TABLE ***
+jp     strncmp
+jp     addDE
+jp     addHL
+jp     upcase
+jp     unsetZ
+jp     intoDE
+jp     intoHL
+jp     writeHLinDE
+jp     findchar
+jp     parseHex
+jp     parseHexPair
+jp     blkSel
+jp     fsFindFN
+jp     fsOpen
+jp     fsGetC
+jp     fsSeek
+jp     fsTell
 
 #include "core.asm"
 #include "parse.asm"
@@ -21,8 +39,7 @@ jp	init
 .equ	FS_RAMSTART	BLOCKDEV_RAMEND
 .equ	FS_HANDLE_COUNT	0
 #include "fs.asm"
-.equ	ZASM_RAMSTART	FS_RAMEND
+#include "user.h"
-#include "zasm/main.asm"
 
 init:
 	di
@@ -34,7 +51,7 @@ init:
 	call	fsOn
 	ld	h, 0	; input blkdev
 	ld	l, 1	; output blkdev
-	call	zasmMain
+	call	USER_CODE
 	; signal the emulator we're done
 	halt
 

tools/emul/zasm/zasm.c

@@ -2,6 +2,7 @@
 #include <stdio.h>
 #include "../libz80/z80.h"
 #include "kernel.h"
+#include "user.h"
 #include "includes.h"
 
 /* zasm reads from a specified blkdev, assemble the file and writes the result
@@ -25,6 +26,7 @@
  */
 
 // in sync with zasm_glue.asm
+#define USER_CODE 0x4800
 #define STDIO_PORT 0x00
 #define STDIN_SEEK_PORT 0x01
 #define FS_DATA_PORT 0x02
@@ -150,6 +152,9 @@ int main()
     for (int i=0; i<sizeof(KERNEL); i++) {
         mem[i] = KERNEL[i];
     }
+    for (int i=0; i<sizeof(USERSPACE); i++) {
+        mem[i+USER_CODE] = USERSPACE[i];
+    }
     for (int i=0; i<sizeof(FSDEV); i++) {
         fsdev[i] = FSDEV[i];
     }

tools/tests/zasm/test7.asm

@@ -1,21 +1,28 @@
-.equ	RAMSTART		0x4000
+.equ    USER_CODE       0x4800
-.equ	ZASM_FIRST_PASS		RAMSTART
+.equ    USER_RAMSTART   0x5800
-.equ	ZASM_LOCAL_PASS		ZASM_FIRST_PASS+1
+.equ    FS_HANDLE_SIZE  8
-.equ	ZASM_CTX_PC		ZASM_LOCAL_PASS+1
-.equ	ZASM_RAMEND		ZASM_CTX_PC+2
 
-#include "core.asm"
+; *** JUMP TABLE ***
-#include "parse.asm"
+.equ    strncmp        0x03
-.equ	BLOCKDEV_RAMSTART	ZASM_RAMEND
+.equ    addDE          0x06
-.equ	BLOCKDEV_COUNT		0
+.equ    addHL          0x09
-#include "blockdev.asm"
+.equ    upcase         0x0c
-
+.equ    unsetZ         0x0f
-.equ	FS_RAMSTART		BLOCKDEV_RAMEND
+.equ    intoDE         0x12
-.equ	FS_HANDLE_COUNT		0
+.equ    intoHL         0x15
-#include "fs.asm"
+.equ    writeHLinDE    0x18
+.equ    findchar       0x1b
+.equ    parseHex       0x1e
+.equ    parseHexPair   0x21
+.equ    blkSel         0x24
+.equ    fsFindFN       0x27
+.equ    fsOpen         0x2a
+.equ    fsGetC         0x2d
+.equ    fsSeek         0x30
+.equ    fsTell         0x33
 
 #include "zasm/util.asm"
-.equ	IO_RAMSTART	ZASM_RAMEND
+.equ	IO_RAMSTART	USER_RAMSTART
 #include "zasm/io.asm"
 .equ	SYM_RAMSTART	IO_RAMEND
 #include "zasm/symbol.asm"