Siko AP09 - Page 15

AP09 Datum 04.05.2000 Art.Nr. 78091 Z.Nr. 8665013 Änd.Stand 140/00 1 5
3 . Byte 5 : Check sum
At the end of the telegram a check sum is
established to check error-free data transmissi-
on. The check sum is an an exclusive-OR-
interconnection of the bytes 1 to 4.
Check sum [byte 5] = [byte 1] XOR [byte 2] XOR
[byte 3] XOR [byte 4]
The telegram received is checked as follows:
[byte 1] XOR [byte 2] XOR [byte 3] XOR [byte 4]
XOR [byte 5] = 0
If the result is not 0, there has probably been a
data transmission error.
Examples:
Reading out positional value of AP09 with address
12 (eg. positional value = 2045,6 (4FE8 hex)).
Master -> AP09 AP09 -> Master
1st byte 0000 1100 (OC) 0000 0000 (00)
2nd byte 0000 0000 (00) 0000 0000 (00)
3rd byte 0000 0000 (00) 0100 1111 (4F)
4th byte 0000 0000 (00) 1110 1000 (E8)
5th byte 0000 1100 (OC) 1010 1011 (AB)
Reading out configuration of an AP09 with address
12 (eg. key function.: reset, 1 decimal point,
CCW increasing values, software V3.07).
Master -> AP09 AP09 -> Master
1st byte 0110 1100 (6C) 0110 1100 (6C)
2nd byte 0000 0000 (00) 0011 0111 (37)
3rd byte 0000 0000 (00) 0000 0001 (01)
4th byte 0010 0000 (20) 0010 0000 (20)
5th byte 0100 1100 (6C) 0111 1010 (7A)
Calibration value programming of address 3 (eg.
calibration value = -100 (FF FF 9C hex; AP09
receipts with value -100).
Master -> AP09 AP09 -> Master
1st byte 1010 0011 (AB) 0010 0011 (23)
2nd byte 1111 1111 (FF) 1111 1111 (FF)
3rd byte 1111 1111 (FF) 1111 1111 (FF)
4th byte 1001 1100 (9C) 1001 1100 (9C)
5th byte 0011 1111 (3F) 1011 1111 (BF)