Parker Hannifin S.p.A. - Divisione S.B.C. LVD User’s Manual
72
Example 10: reading of 4-digit preselector
To change the value of parameter Pr83 by means of a 4-digit preselector. This procedure
involves the use of four digital outputs and four digital inputs:
pin 9 of X6 = output for selection of first preselector digit (least significant)
pin 2 of X6 = output for selection of second preselector digit
pin 10 of X6 = output for selection of third preselector digit
pin 3 of X6 = output for selection of fourth preselector digit
pins 9, 2, 10, 3 of X7 = inputs for reading digit in BCD (pin 9 is the least significant bit;
connection diagram shown on next page).
LD
90.1
OUT
80.0
LD
90.2
OUT
80.1
LD
90.3
OUT
80.2
LD
90.4
OUT
80.3
LD
91.1
MUL
80.73.81
LD
91.2
MUL
80.75.81
LD
91.3
MUL
80.76.81
LD
91.4
MUL
80.77.81
LD
99.13
ADD
81.82.82
LD
91.4
ADD
82.72.83
SUB
82.82.82
LD
91.3
OUT
91.4
LD
91.2
OUT
91.3
LD
91.1
OUT
91.2
LDN
91.2
ANDN 91.3
ANDN 91.4
OUT
91.1
END
MUL
90.1
91.4
91.1
80 73 81
91.3
90.2
91.2
END
90.4
91.1
91.2
91.3
91.4
99.13
91.4
90.3
80.2
80.0
80.1
80.3
MUL
80 75 81
MUL
80 76 81
MUL
80 77 81
ADD
81 82 82
ADD
82 72 83
SUB
82 82 82
91.3
91.4
91.2
91.3
91.1
91.2
Copy 0 digit BCD
copy bit 1 digit BCD
copy bit 2 digit BCD
copy 3 digit BCD
if first digit
calculate units
if second digit
calculate tens
if third digit
calculate hundreds
if fourth digit
calculate thousands
sum the number just calculated in
auxiliary parameter Pr81
if last digit (most significant)
copy final value in Pr83
reset parameter Pr82
update outputs in order to enable
reading of the next number
if last digit already acquired, restart
digit scanning starting from units
program end