TR-Electronic 65 Serie Montageanleitung Seite 163

6.6.7.2 Parity even
The parity bit serves as control bit for the error detection during SSI data
transmissions.
The parity represents the checksum of the bits in the SSI data word. If the SSI data
word contains an odd number of "1", the special bit Parity even = "1" and
supplements the checksum to even parity. The Parity special bit is always defined at
the last digit of the position output. It is calculated from all previous bits. About that,
only one single Parity special bit is possible.
6.6.7.3 Parity odd
The parity bit serves as control bit for the error detection during SSI data
transmissions.
The parity represents the checksum of the bits in the SSI data word. If the SSI data
word contains an even number of "1", the special bit Parity odd = "1" and
supplements the checksum to odd parity. The Parity special bit is always defined at
the last digit of the position output. It is calculated from all previous bits. About that,
only one single Parity special bit is possible.
6.6.7.4 Toggle bit
The Toggle special bit is an additional bit in the SSI format and is attached after the
last data bit of the position output. After each error free SSI transmission sequence the
momentary condition of the Toggle bit is changed. In the event of an error the last
condition of the Toggle bit, before the error was occurred, is maintained.
6.6.7.5 Check sum 28 after 21-28 data bits
The selection "Check sum 28" causes that the measuring system transmits its data
in TR-SSI-format:

Printed in the Federal Republic of Germany
04/25/2022
28 data bits in binary code (MSB bit first)
Check sum 28 after 21 data bits:
-
Number of revolutions = 12 bits, Number of steps per revolutions = 9 bits,
this corresponds to a max. total measuring length of
512 steps/revolution x 4096 revolutions. After output of the position 7
zero bits are attached, in order to keep the data frame of 28 bits.
Check sum 28 after 22 data bits:
-
Number of revolutions = 12 bits, Number of steps per revolutions = 10 bits,
this corresponds to a max. total measuring length of
1024 steps/revolution x 4096 revolutions. After output of the position 6
zero bits are attached, in order to keep the data frame of 28 bits.
Check sum 28 after 23 data bits:
-
Number of revolutions = 12 bits, Number of steps per revolutions = 11 bits,
this corresponds to a max. total measuring length of
2048 steps/revolution x 4096 revolutions. After output of the position 5
zero bits are attached, in order to keep the data frame of 28 bits.
TR-ECE-BA-DGB-0063 v15
 TR-Electronic GmbH 2007, All Rights Reserved
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