switch to sdcc

    - update of the makefile to use sdcc, since it is more popular and
    it's easier to insall on other computers

    - fix of crt0.s (old loader.asm) for the new compiler

    - change of the structure in the source code folder to separate
      betweeen libc and kernel code

9 files changed, 62 insertions, 101 deletions

diff --git a/sw/z80/crt0.s b/sw/z80/crt0.s
new file mode 100644
index 0000000..d0ae3ca
--- /dev/null
+++ b/sw/z80/crt0.s
@@ -0,0 +1,30 @@
+    .area _HEADER (ABS)
+    ;; reset vector
+    .org 0
+    jp init
+    
+    .org 0x08
+    reti
+    .org 0x10
+    reti
+    .org 0x18
+    reti
+    .org 0x20
+    reti
+    .org 0x28
+    reti
+    .org 0x30
+    reti
+    .org 0x38
+    reti
+
+    .org 0x100
+
+init:
+    ;; set stack
+    ld sp,#0xFFFF
+
+    ;; call C main function
+    call _main
+
+.globl _main
diff --git a/sw/z80/crt0.s.old b/sw/z80/crt0.s.old
deleted file mode 100644
index f3bf8e8..0000000
--- a/sw/z80/crt0.s.old
+++ /dev/null
@@ -1,43 +0,0 @@
-    .module crt0
-    .globl  _main
-
-    .area _HEADER (ABS)
-;; reset vector
-    .org 0x0000 
-    jp    init
-    
-    .org 0x0100
-
-init:
-;; Stack at the top of memory.
-    ld    sp,#0xffff                
-
-    ;; initialise global variables
-    call gsinit
-    call _main
-    jp   _exit
-
-    ;; Ordering of segments for the linker.
-    .area _HOME
-    .area _CODE
-    .area     _GSINIT
-    .area     _GSFINAL
-
-    .area _DATA
-    .area     _BSS
-    .area     _HEAP
-
-    .area     _CODE
-__clock::
-    ret
-    
-_exit::
-    ret
-    
-    .area     _GSINIT
-
-gsinit::    
-
-.area _GSFINAL
-    ret
-
diff --git a/sw/z80/kernel.c b/sw/z80/kernel.c
deleted file mode 100644
index 172eee1..0000000
--- a/sw/z80/kernel.c
+++ /dev/null
@@ -1,7 +0,0 @@
-#include "types.h"
-
-
-void main(void)
-{
-
-}
diff --git a/sw/z80/types.h b/sw/z80/kernel/include/types.h
index adde214..adde214 100644
--- a/sw/z80/types.h
+++ b/sw/z80/kernel/include/types.h
diff --git a/sw/z80/kernel/kernel.c b/sw/z80/kernel/kernel.c
new file mode 100644
index 0000000..fe87c3d
--- /dev/null
+++ b/sw/z80/kernel/kernel.c
@@ -0,0 +1,10 @@
+#include "types.h"
+
+
+void main(void)
+{
+    int i, j = 20;
+    for (i = 0; i < 10; i++) {
+        j--;
+    }
+}
diff --git a/sw/z80/loader.asm b/sw/z80/loader.asm
deleted file mode 100644
index 85f5abe..0000000
--- a/sw/z80/loader.asm
+++ /dev/null
@@ -1,18 +0,0 @@
-; C crt0 loader
-;
-    module crt0
-
-; general scope declarations
-    extern _main    ; C code
-
-; startup code
-    org 0000h ; reset vector
-    jp _start
-
-_start:
-    ld sp, 0xffff
-    call _main
-    jp _exit
-
-_exit:
-    ret
diff --git a/sw/z80/makefile b/sw/z80/makefile
index 94646a9..ecdd9a4 100644
--- a/sw/z80/makefile
+++ b/sw/z80/makefile
@@ -2,26 +2,36 @@
 # source code settings
 #
 OSNAME := helvetiOS
-
-CSOURCES 	:= $(wildcard *.c)
-BINARY  	:= $(OSNAME).bin
+ 
+CSOURCES 	:= $(wildcard kernel/*.c) $(wildcard libc/*.c)
+HEXFILE		:= build/$(OSNAME).hex
+BINARY  	:= build/$(OSNAME).bin
 
 ### 
 # compiler settings
-#
-CC 		:= zcc
-CARGS 	:= -Wall -I . -DDEBUG -crt0 loader -asm z80asm -nostdlib
+
+CC 		:= sdcc
+
+CFLAGS	:= -mz80 --no-std-crt0 crt0.rel \
+			-I kernel/include -I libc/include -DDEBUG
+
+LDFLAGS := --code-loc 0x0800 --data-loc 0x8000
 
 all: $(BINARY)
 
 # build binary
-$(BINARY): $(CSOURCES)
-	cp loader.asm loader.opt
-	$(CC) $(CARGS) $(CSOURCES) -o $@
+$(BINARY): $(CSOURCES) crt0.rel
+	mkdir -p build
+	$(CC) $(CFLAGS) $(LDFLSGS) $(CSOURCES) -o $(HEXFILE)
+	xxd -r -p $(HEXFILE) $(BINARY)
+
+crt0.rel: crt0.s
+	sdasz80 -o $<
 
 dis: $(BINARY)
-	z80dasm -a -g 0h $<
+	z80dasm -a -g 0h $< -o $(OSNAME).s
 
 clean:
-	- rm $(BINARY)
-	- rm loader.opt
+	- rm build/*
+	- rm $(OSNAME).s
+	- rm crt0.rel
diff --git a/sw/z80/serial.h b/sw/z80/serial.h
deleted file mode 100644
index 3dc9b18..0000000
--- a/sw/z80/serial.h
+++ /dev/null
@@ -1,15 +0,0 @@
-#ifndef __SERIAL_H__
-#define __SERIAL_H__
-
-#include "types.h"
-
-// define all
-#define USART_BAUD_9600
-#define USART_BAUD_115200
-
-uint8_t usart_registers[8];
-usart_registers = 0x80FF; // TODO: set real address
-
-void usart_init(int16_t baudprescale);
-
-#endif
diff --git a/sw/z80/zcc_opt.def b/sw/z80/zcc_opt.def
deleted file mode 100644
index de830a9..0000000
--- a/sw/z80/zcc_opt.def
+++ /dev/null
@@ -1,6 +0,0 @@
-
-IF !DEFINED_startup
-	defc	DEFINED_startup = 1
-	defc startup = 1
-ENDIF
-