Mitsubishi Electric MELSERVO-J5 User Manual page 304

• Checksum
The checksum is the code which is used by the programmable controller to check for errors in the received absolute position
data. The 6-bit checksum is transmitted following the 32-bit absolute value data.
Calculate the sum of the received absolute position data using the sequence program and compare it with the checksum code
sent from the servo.
The following shows how to calculate the checksum. The checksum will add every ABS 2-bit data inputted to the total. The
checksum is 6-bit data.
(Example) Absolute value data: -10 (FFFFFFF6h)
b
10
b
01
b
11
b
11
b
11
b
11
b
11
b
11
b
11
b
11
b
11
b
11
b
11
b
11
b
11
b
+ 11
b
101101
Therefore, the checksum of -10 is "2Dh".
7 ABSOLUTE POSITION DETECTION SYSTEM
302
7.3 Absolute position detection system by DIO [A]
<Supplement>
Decimal
Hexadecimal FFFF FFF6
Binary
1111 1111 1111 • • • • • • 0110
The binary addition result is 101101
-10
b
.