1 files changed, 78 insertions, 0 deletions
diff --git a/v4.0/src/BIOS/CLOCKSUB.INC b/v4.0/src/BIOS/CLOCKSUB.INC
new file mode 100644
index 0000000..65b6698
--- /dev/null
+++ b/v4.0/src/BIOS/CLOCKSUB.INC
@@ -0,0 +1,78 @@
+;
+;   date_verify loosely checks bcd date values to be in range in bin_date_time
+;
+date_verify:                                ;
+assume  ds:code,es:nothing
+        cmp     byte ptr bin_date_time+0,20h  ; century check
+        ja      date_error                  ; jmp error
+        jz      century_20                  ; jmp in 20th century
+        cmp     byte ptr bin_date_time+0,19h  ; century check
+        jb      date_error                  ; jmp error
+        cmp     byte ptr bin_date_time+1,80h  ; year check
+        jb      date_error                  ; jmp error
+century_20:                                 ;
+        cmp     byte ptr bin_date_time+1,99h  ; year check
+        ja      date_error                  ; jmp error
+        cmp     byte ptr bin_date_time+2,12h  ; month check
+        ja      date_error                  ; jmp error
+        cmp     byte ptr bin_date_time+2,00h  ; month check
+        jbe     date_error                  ; jmp error
+        cmp     byte ptr bin_date_time+3,31h  ; day check
+        ja      date_error                  ; jmp error
+        cmp     byte ptr bin_date_time+3,00h  ; day check
+        jbe     date_error                  ; jmp error
+        clc                                 ; set success flag
+        ret                                 ;
+date_error:                                 ;
+        stc                                 ; set error flag
+        ret                                 ;
+;
+; time_verify very loosely checks bcd date values to be in range in bin_date_time
+;
+time_verify:
+assume  ds:code,es:nothing
+        cmp     byte ptr bin_date_time+0,24H
+        ja      time_error
+        cmp     byte ptr bin_date_time+1,59H
+        ja      time_error
+        cmp     byte ptr bin_date_time+2,59H
+        ja      time_error
+        clc
+        ret
+time_error:
+        stc
+        ret
+;
+;   bcd_verify checks values in bin_date_time to be valid
+;   bcd numerals.  carry set if any nibble out of range
+;
+bcd_verify:                     ;
+assume  ds:code,es:nothing
+        mov     cx,4            ; 4 bytes to check
+        mov     bx,offset bin_date_time   ;
+bv_loop:                        ;
+        mov     al,[bx]         ; get a bcd number (0..99)
+        mov     ah,al           ;
+        and     ax,0f00fh       ; 10's place in high ah, 1's in al
+        cmp     al,10           ; is 1's place in range?
+        ja      bv_error        ; jmp out of range
+        shr     ah,1            ; swap nibbles
+        shr     ah,1            ; ...
+        shr     ah,1            ; ...
+        shr     ah,1            ; ...
+        and     ah,0fh          ; get rid of any erroneous bits
+        cmp     ah,10           ; is 10's place in range
+        ja      bv_error        ; jmp out of range
+        inc     bx              ; next byte
+        dec     cx              ;
+        jnz     bv_loop         ;
+        clc                     ; set success flag
+        ret                     ;
+bv_error:                       ;
+        stc                     ; set error flag
+        ret                     ;
+;
+; Dos 3.30 - The real time clock structures were moved to msbio2.asm
+;

diff --git a/v4.0/src/BIOS/CLOCKSUB.INC b/v4.0/src/BIOS/CLOCKSUB.INC new file mode 100644 index 0000000..65b6698 --- /dev/null +++ b/v4.0/src/BIOS/CLOCKSUB.INC
@@ -0,0 +1,78 @@
	1	;
	2	; date_verify loosely checks bcd date values to be in range in bin_date_time
	3	;
	4	date_verify: ;
	5	assume ds:code,es:nothing
	6	cmp byte ptr bin_date_time+0,20h ; century check
	7	ja date_error ; jmp error
	8	jz century_20 ; jmp in 20th century
	9	cmp byte ptr bin_date_time+0,19h ; century check
	10	jb date_error ; jmp error
	11	cmp byte ptr bin_date_time+1,80h ; year check
	12	jb date_error ; jmp error
	13	century_20: ;
	14	cmp byte ptr bin_date_time+1,99h ; year check
	15	ja date_error ; jmp error
	16	cmp byte ptr bin_date_time+2,12h ; month check
	17	ja date_error ; jmp error
	18	cmp byte ptr bin_date_time+2,00h ; month check
	19	jbe date_error ; jmp error
	20	cmp byte ptr bin_date_time+3,31h ; day check
	21	ja date_error ; jmp error
	22	cmp byte ptr bin_date_time+3,00h ; day check
	23	jbe date_error ; jmp error
	24	clc ; set success flag
	25	ret ;
	26	date_error: ;
	27	stc ; set error flag
	28	ret ;
	29
	30	;
	31	; time_verify very loosely checks bcd date values to be in range in bin_date_time
	32	;
	33	time_verify:
	34	assume ds:code,es:nothing
	35	cmp byte ptr bin_date_time+0,24H
	36	ja time_error
	37	cmp byte ptr bin_date_time+1,59H
	38	ja time_error
	39	cmp byte ptr bin_date_time+2,59H
	40	ja time_error
	41	clc
	42	ret
	43	time_error:
	44	stc
	45	ret
	46
	47	;
	48	; bcd_verify checks values in bin_date_time to be valid
	49	; bcd numerals. carry set if any nibble out of range
	50	;
	51	bcd_verify: ;
	52	assume ds:code,es:nothing
	53	mov cx,4 ; 4 bytes to check
	54	mov bx,offset bin_date_time ;
	55	bv_loop: ;
	56	mov al,[bx] ; get a bcd number (0..99)
	57	mov ah,al ;
	58	and ax,0f00fh ; 10's place in high ah, 1's in al
	59	cmp al,10 ; is 1's place in range?
	60	ja bv_error ; jmp out of range
	61	shr ah,1 ; swap nibbles
	62	shr ah,1 ; ...
	63	shr ah,1 ; ...
	64	shr ah,1 ; ...
	65	and ah,0fh ; get rid of any erroneous bits
	66	cmp ah,10 ; is 10's place in range
	67	ja bv_error ; jmp out of range
	68	inc bx ; next byte
	69	dec cx ;
	70	jnz bv_loop ;
	71	clc ; set success flag
	72	ret ;
	73	bv_error: ;
	74	stc ; set error flag
	75	ret ;
	76	;
	77	; Dos 3.30 - The real time clock structures were moved to msbio2.asm
	78	;