Operation; Messages; Imd_Info; Imd_Request - Bender ISOMETER iso165C Manual

6. Operation

6.1 Messages

Communication between a requesting instance in the vehicle environment and the ISO-
METER® takes place over the HS-CAN bus. The ISOMETER® can handle the following
HS-CAN messages:
Message CAN-ID

IMD_Info

0x37 Tx

IMD_Request

0x22 Rx
IMD_Response 0x23 Tx
The messages contain either DataByte or DataWord values. The byte order for the Data-
Word values is:
DataByte
Byte order
7............0
Byte order DataWord
LowByte HighByte
7............0 15...........8
6.2 IMD_Info
IMD_Info is cyclically sent once per second from the ISOMETER® and contains data values
that represent the insulation resistance and the internal operating states of the VIFC and
IMC.
Byte no. 0 1 2
D_IMC_R_ISO D_IMC_STATUS
Data value descriptions can be found in Chapter 7.3 on page
The following example contains IMC status information:
CAN-ID
DLC* Data1 Data2
(Info)
0x37 0x6 dc dc
*DLC = Data Length Code
15
Direction Cyclic
1s
-
-
3 4 5 6
D_VIFC_STATUS Unused Unused
20.
Data3 Data4 Data5
IMC_STATUS_LS
IMC_STATUS_MSB dc
B
Operation
6.3 IMD_Request
IMD_Request is a request to the ISOMETER® and will always generate an answer message
IMD_Response. It can handle Control (CTL), SET and GET commands.
A request has the following format:
Byte 0
CMD Data1
DataWord1
Definitions of DataWord1 and DataWord2 for different commands can be found in
on page 17.
For synchronous processing of the asynchronously received IMD_Request commands,
the VIFC implements a queue which operates on the First In, First Out (FIFO) principle. If
the queue is full, an error response is generated and the request is dropped by the ISO-
METER®. The "Queue full" error response is not generated for every single request and
may be generated only after a certain number of requests have been made.
To avoid processing commands that could mistakenly modify the system configuration
during standard operation, the ISOMETER® has implemented a locking mechanism. The
locking state can be changed with the command S_VIFC_CTL_LOCK.
CMD
0x21 S_IMC_CTL_SELFTEST
0xC8 S_VIFC_CTL_IMC_RESET
0xCA S_VIFC_CTL_LOCK
7
0xCB S_VIFC_CTL_MEASUREMENT
CMD DBC command description
0x28 S_IMC_SET_R_ISO_ERR_THR
0x29 S_IMC_SET_R_ISO_WRN_THR
Data6
0x2B S_IMC_SET_MEAN_FACTOR
0xD2 S_VIFC_SET_HV_RELAIS
dc
1 2 3 4 5
Data2 Data3 Data4
Unused
DataWord2
Control (CTL) commands
DBC command description Locked
SET commands
Locked
X
X
X
iso165C_D00154_03_M_XXEN/01.2019
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Unused Unused
"Command descriptions"