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ams Datasheet

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[v1-00] 2015-Apr-01

HLS-440P − Electrical Inter face

CAN Bus Interface

This section describes the CAN bus interface that is available in

some variants of HLS-440P.

Physical Interface

The physical interface is two-wire balanced. It is a high speed

CAN interface (ISO 11898-2) with bus bit rate at 500 kbit/s.

Type A: 120 Ohm CAN bus termination

Type B: no termination

CAN Matrix HLS-440P

HLS-440P will send the first CAN message 0.1 s after start-up.

The repetition rate of the CAN message is 100ms ±2ms. The first

prior to that will have the "Not_ready" bit set, indicating that

the concentration value of the message is not valid.

In case of a warm restart (<5s) error category 1 will be set for 10 s.

The Msg Counter increments with each CAN message.

Each CAN message is sent twice. The first time it is sent with ID

1592 (0x0638) for type A and 1600 (0x0640) for type B. The

second time it is sent with ID 1595 (0x063B) for type A and ID

1603 (0x0643) for type B. The second time all bytes excluding

byte 7 are inverted. Byte 7 has the fix value 170 (hex AA) in the

second message.