Initial work on XOS

xiasm.bas

@@ -42,7 +42,7 @@ sub do_asm(filename as string, argi as integer)
 
     if udidx > 0 then       ' we have a need for a fix-up pass
 
-        'print ">>> PASS 2 [INFO]:   Attempting to resolve "; trim(str(udidx)); " symbol(s) left over from pass 1"
+        print ">>> PASS 2 [INFO]:   Attempting to resolve "; trim(str(udidx)); " symbol(s) left over from pass 1"
 
         dim i as integer
         dim e as undef_entry
@@ -61,7 +61,7 @@ sub do_asm(filename as string, argi as integer)
                 print "FATAL UNRESOLVED SYMBOL "; e.e_key
                 end
             else
-                'print ">>> PASS 2 [INFO]:   Resolved symbol "; e.e_key; " (symbol found at offset "; hex(f.offset); "h, inserted at fix-up offset "; hex(fixup_offset); "h)"
+                print ">>> PASS 2 [INFO]:   Resolved symbol "; e.e_key; " (symbol found at offset "; hex(f.offset); "h, inserted at fix-up offset "; hex(fixup_offset); "h)"
                 st_write_word argi, fixup_offset, f.offset
             end if   
                                                
@@ -146,7 +146,7 @@ sub initial_pass(page_number as ushort)
                 else
                     asm_offset = get_lexer_entry(1).intval
                 end if          
-                'print ">>> PASS 1 [INFO]:   Program ORIGIN set to offset "; hex(asm_offset)
+                print ">>> PASS 1 [INFO]:   Program ORIGIN set to offset "; hex(asm_offset)
 				origin = asm_offset
             case "EQU"
                 t_sym.e_key = get_lexer_entry(1).strval
@@ -205,7 +205,7 @@ sub initial_pass(page_number as ushort)
                 fixup_flag = 0
 	            ts = expand_macros(input_lines(i))
 	
-	            'print ">>> PASS 1 [OUTPUT]: "; ilxi_pad_left(hex(asm_offset), "0", 4); ":  "; ts
+	            print ">>> PASS 1 [OUTPUT]: "; ilxi_pad_left(hex(asm_offset), "0", 4); ":  "; ts
 	
 	            asm_assemble ts
                 asm_offset += 1
@@ -301,7 +301,7 @@ function expand_macros(input_string as string) as string
                         ' resolution until next pass if not resolved
                         '
                         if symbol.resolved = 0 then
-                            'print ">>> PASS 1 [INFO]:   Deferring resolution of '"; macro_name; "' until next pass"
+                            print ">>> PASS 1 [INFO]:   Deferring resolution of '"; macro_name; "' until next pass"
                             
                             dim uent as undef_entry
                         

xos/kernel.xa

+;
+;  ILXI eXtended Operating System - XOS 
+;   Version 0.1
+;   
+;   Copyright (C) 2016 Coherent Logic Development
+;
+;   kernel.xa - kernel routines
+;
+    PROGRAM TITLE 'XOS'
+    ORIGIN 0
+
+    EQU PG_SYS 0                ; system code page
+    EQU PG_VID 1                ; video buffer page
+    EQU PG_DAT 0                ; system data page
+    EQU PG_DTA 2                ; disk transfer area
+    EQU PG_STK 10               ; stack page
+    
+    BRANCH WORD {__BOOT}        ; skip decls, branch to __BOOT
+
+    VAR WORD CON_PTR 1          ; console pointer
+    VAR ZSTRING BOOTMSG "ILXI XOS 0.1"
+
+;****
+; CONSOLE_INIT
+;  Initialize the XOS console
+;
+LABEL CONSOLE_INIT              
+    OUT 0,1                     ; enable cursor
+    OUT 1,25                    ; set console cycle to 25ms
+    OUT 2,0                     ; no horizontal offset
+    OUT 3,0                     ; no vertical offset
+    COPY WORD (#{CON_PTR}),1    ; initialize console pointer
+    SRET
+
+;****
+; CONSOLE_PRINT
+;  Print string pointed to by SS:SI 
+;
+LABEL CONSOLE_PRINT
+    PUSH WORD %BP               ; preserve BP
+    COPY WORD %BP,%SO           ; copy stack offset to base ptr
+
+    PUSH WORD %SS               ; preserve SS
+    PUSH WORD %DS               ; preserve DS
+    PUSH WORD %DI               ; preserve DI
+    
+    COPY WORD %DS,{PG_VID}      ; destination page = video page
+    COPY WORD %DI,#{CON_PTR}    ; destination offset = CON_PTR
+
+    CPSZ                        ; copy SS:SI to video buffer
+
+    ADD WORD (#{CON_PTR}),%DI   ; update console pointer
+    
+    POP WORD %DI                ; restore DI
+    POP WORD %DS                ; restore DS
+    POP WORD %SS                ; restore SS
+    POP WORD %BP                ; restore BP
+
+    SRET
+    
+LABEL __BOOT
+    COPY WORD %DP,{PG_DAT}      ; initialize data page
+    COPY WORD %SP,{PG_STK}      ; initialize stack page
+    
+    COPY WORD %SS,%DP           ; point SS:SI to BOOTMSG
+    COPY WORD %SI,{BOOTMSG}
+    SCALL WORD {CONSOLE_PRINT}  ; call print routine
+