E981.07 Datasheet, PDF (41/46 Pages) ELMOS Semiconductor AG – Two independent operating channels

Two Channel Sensor Interface PSI5
ADVANCE PRODUCT INFORMATION JUL 26, 2011
5.2.7.3 Message Protocol Format
E981.07
As shown in Figure 5.2-5 each transmitted telegram consists of 2 start bits, 10 data bits and 1 parity bit. Data
bits are transferred with LSB first. Both start bits are logical '0'. The parity is even and is calculated over data
bits D0 to D9. The time per bit is 8 µs and consequently the complete 13-bit data frame is transferred in 104µs.
X X S1 S2 D0 D1 D2 D3 D4 D5 D6 D7 D8 D9 P
Figure 5.2-5: Message Protocol Format
5.2.7.4 Manchester Decoder
The Manchester Decoder tolerates satellite communication as per PSI5 specification for P10P-500/3L mode of
operation. The received data bits are first stored in a receive register in order to check the consistency of the
data word.
Depending on the time slot where the telegram is transmitted, the received data word is stored into the
appropriate sensor data register (see 5.2.5.4).
A Manchester Error (ME) is set if two valid start bits are detected and the transmitted telegram has not exactly
13 valid bits or the bit timing is incorrect.
A transmitted telegram which is not within one of the three time slots result also into a Manchester Error:
Start of
End of
Transmission within Transmission within
Manchester Error is stored
in sensor data register
Time slot 1
Time slot 2
A
Time slot 2
Time slot 3
B
Time slot 3
After time slot 3
C
After time slot 3
After time slot 3
C
A Data Error (DE) is set when the parity bit is wrong.
ELMOS Semiconductor AG
Data Sheet 41 / 45
QM-No.: 25DS0050E.00
This document contains information on a new product. ELMOS Semiconductor AG reserves the right to change specifications and information herein without notice.