Z85233 Datasheet, PDF (222/317 Pages) Zilog, Inc. – The Zilog SCC Serial Communication Controller

INITIALIZATION ROUTINE FOR Z-SCC
Application Note
SCC in Binary Synchronous Communications
0034
GLOBAL INIT
ENTRY
PROCEDURE
9
0634
2100
LD
R0, #15
!NO.OF PORTS TO WRITE TO!
0036
000F
0038
7602
LDA R2, SCCTAB !ADDRESS OF DATA FOR PORTS!
003A 004E'
003C 2101
ALOOP: LD
R1, #WR0A
003E FE21
0040
0029
ADDB RL1, @R2
0042
A920
INC
R2
0044
3A22
OUTIB @Rl, @R2,R0 !POINT TO WR0A,WR1A ETC THRO LOOP!
0046
0018
0048
8D04
TEST R0
!END OF LOOP?!
004A EEF8
JR
NZ, ALOOP !NO, KEEP LOOPING!
004C 9E08
RET
004E 12
SCCTAB: BVAL 2*9
004F CO
BVAL %C0
!WR9=HARDWARE RESET!
0050
08
BVAL 2*4
0051
10
BVAL %10
!WR4=X1 CLK, 16 BIT SYNC MODE!
0052
14
BVAL 2*10
0053
00
BVAL 0
!WRIO=CRC PRESET ZERO, NRZ,16 BIT SYNC!
0054
0C
BVAL 2*6
0055
AB
BVAL %AB
!WR6=ANY SYNC CHAR %AB!
0056
0E
BVAL 2*7
0057
CD
BVAL %CD
!WR7=ANY SYNC CHARR %CD!
0058
04
BVAL 2*2
0059
20
BVAL %20
!WR2=NT VECTOR %20!
005A 16
BVAL 2*11
005B 16
BVAL %16
!WR11=TxCLOCK & TRxC OUT=BRG OUT!
005C 18
BVAL 2*12
005D CE
BVAL %CE
!WR12= LOWER TC=%CE!
005E IA
BVAL. 2*13
005F 00
BVAL 0
!WR13= UPPER TC=01
0060
1C
BVAL 2*14
0061
03
BVAL %03
!WRI4=BRG ON, ITS SRC=PCLK!
0062
1E
BVAL 2*15
0063
00
BVAL %00
!WRI5=NO EXT INT EN.!
0064
0A
BVAL 2*5
0065
64
BVAL %64
!WR5= TX 8 BITS/CHAR, CRC-16!
0066
06
BVAL 2*3
0067
Cl
BVAL &CI
IWR3=RX 8 BITS/CHAR, REC ENABLE!
0068
02
BVAL 2*1
0069
08
BVAL %C1
!WR1=RxINT ON 1ST OR SP COND!
!EXT INT DISABLE!
006A 12
BVAL 2*9
006B 09
BVAL %09
!WR9=MIE, VIS, STATUS LOW!
006C
END INIT
UM010901-0601
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