IBM XT 5160 Technical Reference page 226

AX HAS THE VALUE READ IN FROM THE 6845
I BM Persona I Computer MACRO Assemb I er Vers
i
on 2.00
VIDEO ---- 01/10/86 VIDEO DISPLAY BIOS
V4:
DIV
BYTE PTR OCRT_COLS
MOV DH,AL
MOV DL;AH
SAL AL,CL
MOV CH,AL
MOV
BL,AH
XOR
BH,BH
SAL BX,CL
V5:
MOV AH,I
V6:
PUSH
OX
MOV
DX,OADDR_6845
ADD
DX,7
OUT
DX,AL
POP OX
V7:
POP BP
POP 01
POP SI
POP OS
POP
OS
POP
OS
POP OS
POP ES
IRET
READ_LPEN ENDP
CODE ENDS
END
5-79
DIVISOR FOR GRAPHICS
DETERM I NE ROW ( AL ) AND COLUMN ( AH )
AL RANGE 0-99, AH RANGE 0-39
COLUMN VALUE FOR RETURN
ROW VALUE
DIVIDE BY 4
FOR VALUE IN 0-24 RANGE
LIGHT_PEN_RETURN_SET
CONVERT TO CORRECT PAGE OR I GIN
IF POS I T I VE, DETERM I NE MODE
<0 PLAYS AS 0
; ADDRESS REG I STER
; SECOND DATA REG I STER
POINT TO DATA REGISTER
I/O DELAY
GET SECOND DATA VALUE
AX HAS INPUT VALUE
; MODE VALUE TO BX
; DETERM I NE AMOUNT TO SUBTRACT
; TAKE I T AWAY
; 0 I SCARD SAVED BX, CX ,OX
DETERM I NE MODE
SET • 8 SHIFT COUNT
DETERM I NE I F GRAPH I CS OR ALPHA
ALPHA_PEN
; ALPHA_PEN
; SAVE ROW VALUE IN CH
; ·2 FOR EVEN/ODD FIELD
; COLUMN VALUE TO BX
; MULTIPLY BY 8 FOR MEDIUM RES
; DETERM I NE MED I UM OR HIGH RES
; NOT HIGH RES
; SHIFT VALUE FOR HIGH RES
; COLUMN VALUE TIMES 2 FOR HIGH RES
; NOT HIGH RES
; MULTIPLY-·,6 FOR HIGH RES
ALPHA PEN
DETERM I NE ROW, COLUMN VALUE
ROWS TO DH
; COLS TO DL
; MULTIPLY ROWS • 8
; GET RASTER VALUE TO RETURN REG I STER
; COLUMN VALUE
; TO BX
LIGHT PEN RETURN SET
I NO I CATE EVERY TH I NG SET
; LIGHT PEN RETURN
; SAVE RETURN VALUE (IN CASE)
; GET BASE ADDRESS
; PO I NT TO RESET PARM
; ADDRESS, NOT DATA, IS IMPORTANT
; RECOVER VALUE
; RETURN_NO_RESET
1-18
01-10-86
VIDEO (01/10/86)
AL,DX
AH,CH
CL,3
OCRT MODE,4
V4 -
OCRT MODE,7
V4 -
BX,CL
CH,AL
CH,CH
BL,AH
BH,BH
OCRT MODE,6
V3 -
CL,4
AH,I
DL,AH
DH,AL
DH,I
DH,I
SHORT V5
DL,40
DL
ox
AH
AL,AH
DX,AL
OX
BL ,OCRT MODE
BH,BH -
BL,CS:Vl [BX]
AX,BX
BX,OCRT START
BX,I -
AX,BX
V2
AX,AX
GRAPH I CS MODE
ALPHA MODE ON LIGHT PEN
MOV
DIV
DETERM I NE ALPHA CHAR POS I T I ON
MOV
CMP
JB
CMP
JE
MOV
ADD
MOV
SUB
CMP
JNE
MOV
SAL
SHL
DETERM I NE GRAPH I CROW POS I T I ON
DETERM I NE MODE OF OPERAT I ON
MOV
MOV
SHR
SHR
JMP
MOV
SUB
MOV
SUB
MOV
SHR
SUB
JNS
SUB
DEC
INC
MOV
OUT
INC
NOP
IN
MOV
V3:
V2:
1901 07AB 4A
1902 07AC FE C4
1903 07AE 8A C4
1904 07BO EE
1:g~ g~~~ :~
1907 07B3 EC
1,908 07B4 8A E5
1909
1910
1911
1912 07B6 8A IE 0049 R
1913 07BA 2A FF
191 4 07BC 2E: 8A 9F 0770 R
1915 07Cl 2B C3
1916 07C3 8B IE 004E R
19 17 07 C 7 0 1 EB
1918 07C9 2B C3
1919 07CB 79 02
1920.07CD 2B CO
1921
1922
1923
1924 07CF
1925 07CF Bl 03
1926 0701 80 3E 0049 R 04
1927 0706 72 2A
1928 0708 80 3E 0049 R 07
1929 0700 74 23
1930
1931
1932
1933 07DF B2 28
1934 07El F6 F2
1935
1936
1937
1938 07E3 8A E8
1939 07E5 02 ED
1940 07E7 8A DC
1941 07E9 2A FF
1942 07EB 80 3E 0049 R 06
1943 07FO 75 04
1944 07F2 Bl 04
1945 07F4 DO E4
1946 07F6
1947 07F6 03 E3
1948
1949
1950
1951 07F8 8A 04
1952 07FA 8A FO
1953 07FC DO EE
1954 07FE DO EE
1955 0800 EB 12
1956
1957
1958
1959 0802
1960 0802 F6 36 004A R
1961 0806 8A FO
1962 0808 8A 04
1963 080A 02 EO
1964 080C 8A E8
1965 080E 8A DC
1966 0810 32 FF
1967 0812 03 E3
1968 0814
1969 0814 B4 01
1970 0816
1971 0816 52
1972 0817 8B 16 0063 R
1973 081B 83 C2 07
1974 081E EE
1975 081F 5A
1976 0820
1977 0820 50
1978 0821 5F
1979 0822 5E
1980 0823 1F
1981 0824 IF
1982 0825 1F
1983 0826 1F
1984 0827 07
1985 0828 CF
1986 0829
1987 0829
1988