NorthStar HSIO-4 User's & Technical Manual page 53

0021
0021
0021
0021 CD0000
0024 CD5100
0027 FE10
0029 20F6
002B CD5100
002E
FE16
28EF
0030
0032 FE02
20EB
0034
0036
0036
0036
CD5100
0036
0039 FE10
003B 2010
003D CD5100
0040 FE10
2809
0042
0044 FE16
28EE
0046
0048 FE03
00 4A C8
004B 18E9
004D
004D 77
00 4E 23
18E5
004F
0051
0051
DB13
0053 E602
0055 28FA
0057 DB12
0059 C9
North Star HSIO-4
•
r
; Synchronous input routine (RAM address in HL)
•
9
SYNI CALL INIT
CALL GETCH
CPI DLE
JRNZ SYNI
CALL GETCH
CPI SYN
JRZ SYNI
CPI STX
JRNZ SYNI
r
i
Transfer message into RAM
•
9
SDATA CALL GETCH
DLE
CPI
JRNZ RAMLD
CALL GETCH
CPI DLE
JRZ RAMLD
SYN
CPI
JRZ
SDATA
ETX
CPI
RZ
•
f
JR SDATA
•
9
RAMLD MOV M, A
H
INX
JR SDATA
•
9
GETCH IN
CTRL
ANI RXRDY
JRZ GETCH
IN DATA
RET
Set USART into hunt mode and
•
r
reset errors
•
9
Wait for DLE to appear
•
r
• i
,
If SYNC
f Check for start of text,
•
if bad, try again
•
If not DLE then data
•
9
Get second char of DLE seq
•
9
If DLE-DLE then use one
•
9
of them as data
•
9
Check for padding (SYNC chars)
•
9
ignore if it is
•
9
End yet ?
•
9
If not done, then bad DLE
•
9
sequence found, ignore it
•
9
Insert byte into RAM at (HL)
•
9
Get next byte
•
9
Get char from serial port
•
9
Wait till done
•
9
48 User/Technical Manual
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