Components and Operation
English, Revision 02, Date: 20.01.2015
13
Sum of A
43
, and P results in 0 (Mod256).
Example:
Bit sequence:
0000 0111 0000 1011
Transponder code 16 bit) 070
hex
in the tran-
sponder
The following bytes will be output:
The hexadecimal sum over 0,7, 0B, EE results in (1)00
hex.
2.2.6
Positioning Pulse
On crossing the center line the positioning pulse will be released. Its duration is
100 ms. Once the positioning pulse has been activated, 24 V will be switched to the
corresponding output with a current limitation of 20 mA.
NOTE!
Refer to chapter 1.3.3 „Signals and Timing“ on page 8 for the tim-
ing of the PosiPuls.
2.2.7
Resetting the antenna
The reset of the antenna is triggered as soon as it receives the sign DC2 (012h) with
the right parity. Then the antenna confirms the reception of this command by sending
an answer telegram. After that the programm resets all intern variables. Any other
signs or transmission errors are ignored.
This answer telegram is built up as follows (binary coded):
-
1.
’StartofHeader’=01h
-
2. data byte with the bits 15...8 (bit 8 = LSB of the byte) of the last read code
-
3. data byte with the bits 7...0 (bit 0 =LSB of the byte) of the last read code
-
4. check byte: the sum of the telegram identification, the data bytes and this
check byte equals 0.
If the ASCII coded output is activated, the code will be displayed as shown in table 5
on page 12 . If no transponder has been read until the card is resetted, the value
000h
will be put out.
Character
Hex-Value
STX
02
A43
07
A21
0B
P
EE
Table 6
Example telegram binary coded
