Lexicon MPX-1 - Page 25

41AE CD2341 RD256:
CALL
PUTST
41B1 2EOO
HVI
L,O
;zero L reg.
41B3 110001
LXI
D,BUFFER
;DE gets BUFFER address
41B6 7E
RD2: MOV A,t1 ;get byte
41B7 12
STAX D ;store it in buffer
41B8 lC
INR E
41B9 2C
INR
L
41BA C2B641
JNZ RD2
41BD C9
RET
;This subroutine writes 256 bytes
from BUFFER to external
;memory pointed to by DESTAD.
41BE CD3641 WR256:
CALL PUTDST
41Cl 2EOO MVI
L,O
41C3 110001
LXI
D,BUFFER
41C6 lA
WR2: LDAX
D
;A gets byte from buffer
41C7 77
MOV M,A
41CB lC
INR
E
41C9 2C
INR
L
41CA C2C641
JNZ WR2
41CD C9
RET
;The actual commands start below:
;Command does nothing. but is useful anyway.
41CE C9
NOPR: RET
;Command to set OCWI (Mask Byte)
41CF 3AA200
41D2 320180
41D5 C9
SETMSK: LDA
STA
RET
.~TRTAD
INTCLB
;Get the mask byte
;Command to send EOI to interrupt controller (OCW2)
41D6 3AA200
41D9 320080
41DC C9
SETEOI: LDA
STA
RET
STRTAD
INTCLA
;get the EOl byte
;Command to read the IR and IS registers in the Interrupt
"'~.~11..... Puts IR in RESULT! and IS in RESULT2.