Protocol, Information Interface; Protocol, K-Line; Pulse Interfaces B6, B7, B8, D6; Speed-Coding Outputs B6, B7 - Bosch Intellic EFAS-4.10 Workshop Manual

The serial interface on pin D7 is pre-configured as a diagnostic interface. It can alternatively be used to connect an e-tachometer
with K-line interface if the vehicle in which EFAS is to be installed does not have a CAN bus for connecting the tachometer/
instrument cluster to the tachograph.
13.2.1

Protocol, information interface

According to (EC) regulation no. 1360/2002, margin no. 153, the tachograph must have an interface for cyclical data transmis-
sion. The data is prepared by means of a simple protocol at the so-called info-interface.
The following data is required:
y Current date and time (UTC)
y Vehicle speed
y
Mileage
y The currently selected activity of the driver and of the co-driver
y Information as to whether a smart-card is inserted into the driver's or co-driver's slot
y
Information regarding any smart-card which is inserted (card number and issuing member state)
The data transfer rate on the serial info interface is 10.4 kbps. The data are sent cyclically every second. Observe the corre-
sponding parameter RDI=0xFD26 for selection of the protocol at this interface. Irrespective of the input voltage range of the
tachograph (12 V or 24 V), the parameter setting can limit the data signal at connector D8 to 10 V (low=0 V, high=10 V).
13.2.2

Protocol, k-line

At this interface, as per ISO 14230, the standard UDS protocol according to ISO 14229 is available for diagnostics and for reading
parameters. It is not possible to calibrate the recording equipment via this interface. The data transfer rate on the K-line is
10.4 kbps. Observe the corresponding parameter RDI=0xFD26 for selection of the protocol at this interface.
13.3

Pulse interfaces B6, B7, B8, D6

EFAS offers pulses for controlling external displays at its outputs B6, B7, B8 and D6.
These pulses are in accordance with ISO 16844 format.
B6, B7, B8 each have an active driver that provides the standard low level of <1.5 V and the high level of >5.5 V at 1 mA.
13.3.1

Speed-coding outputs B6, B7

At its interfaces B6, B7 and D6, EFAS codes the travel speed ('v') of the EFAS as a function of the frequency of the input pulse at
B3, taking into account the w/k calibration factor, which is why this pulse is also referred to as the v pulse or speed pulse.
Level monitoring can be activated for output B7 to ensure that connected control units do not transmit speed information that
has been manipulated by a short-circuit.
Short-circuit monitoring is activated e.g. in the EFAS Service Tool via the parameter "Short-circuit monitoring B7". B7 has a limited
output level of 10 V. Also B6 has only a limited level.
Workshop Manual
Smart Tachograph EFAS-4.10/4.11
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