File DECADD

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[DECADD
[DECIMAL ADDITION
[USES DECBASE
[JMP 1A
[ADDR ADDEND
[ADDR ADDEND
[ADDR SUM
[#1B-ADDR BUFFER AREA
[1L=#DIGITS
[1L,1B SET IN DECBASE
[XR 1 TO 12
#1A CLR
ADD 0
JMP 1N
ROLi1  [SAVE SIGN2
SCR 1
STAi
  0
COM
ADD 1N+104
STAi
 0
APOi
 COM
STC 6 [-|DIFF|
RORi1
STA
1N+122 [SIGN2
BCO 2
SCR 13
STC 4 [XOR SIGNS
ADD p-16+4
XSK 4 [SKIP SIGNS NOT =
 JMP p+3
AZEi
 JMP p+25 [EXPS =
APO
 JMP p+44
[ ARG1>ARG2
 LDA
 2
SET 2
 3
STC 3
LDA 3 [RECOVER SIGN1
BCL i
3777
STC 1N+122 [RESULT SIGN
JMP p+35
[ SHIFT SMALLER
 LDHi3 [LARGER
STAi7 [RESULT
XSKi6
 APO [SKIP
JMP p+44 [SHIFTED ENOUGH
XSKi10
 JMP p-6
JMP 1N+32 [EXIT
[ FIND LARGER MANTISSA FOR MINUEND
 SETi5
-1L [#DIGITS
SET 11
 2
SET 12
 3
 LDHi11 [ARG1
STC 0
LDHi12 [ARG2
COM
ADD 0  [ARG1-ARG2
AZE
 JMP p-36-2
XSKi5
 JMP p-10
ADD p [FORCE UNDERFLOW [>2000+1L,BIT <3777]
JMP 1N+31 [STC 1N+104,EXIT
[
[ ARG2>ARG1
 LDA
 p-71    [EXP2
STC 1N+104 [RESULT EXP
 ADD p-73+1 [=COM
XSK 4 [SKIP SIGNS NOT =
ADD 1N+62 [-1 MAKES NOP
STC p+3+3
[7=1B, 10=-1L
XSK 6
 JMP p-41
 LDHi3 [LARGER
STC 0
LDHi2 [SMALLER
 NOP  [OR COM
ADD 0
STAi7 [SUM
 XSKi10
 JMP p-7
[PROPAGATE CARRIES IN RESULT BUFFER
 SETi10
-1L
[ 7 POINTS TO RIGHT END RESULT
 LDA 7
AZEi
 JMP p+16 [ZERO DIGIT
APO
 JMP p+33 [NEG DIGIT
ADAi
 -11
APOi
 JMP p+13 [DIGIT >9
LDAi
-1
ADM
 7
 XSKi10
 JMP p-16 [NEXT DIGIT TO LEFT
JMP 1N+32 [EXIT
[ ZERO DIGIT
 CLR
STA 7
JMP p-5-4
[
[ DIGIT >9
 ADD 1N+62 [-1
AZEi
 CLR
STA 7
LDAi
 -1
ADD 7
STC 7
ADD 1N+51 [1
ADM 7
JMP p-20
[
XSKi10 [NOSKIP
 ADD 1N+150 [12
AZEi
 CLR
STA 7
LDAi
 -1
ADM
 7
LDA 7
ADD 1N+62 [-1
AZEi
 CLR
APO
 JMP p-15-1
STA 7
JMP p-41
[END DECADD
[JAN 8|15|69



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