PMU CAN communication to ViPec i88

[Sute]

Hi,

Just purchased PMU 16 to my project car. My ECU is ViPec i88 / Link G4+ that has CAN Bus. I would like to know how to connect PMU and ECU through CAN and make power control via CAN. Done quite a lot ECU stuff but have avoided CAN communication basics with success..

There´s info how to make basic CAN settings to Ecumaster ECUs but not other ECUs.

Thanks a lot.

[jgm]

Hi,

Looking at the ViPec help, there are two ways to communicate ViPec88 to PMU.

1. You can use some predefined ViPec standard stream. For example "Generic Dash 2" can be read by PMU directly.
Below is a screenshot from ViPec help. GenericDash2 provides some basic channels like RPM. But it lacks some information about the state of outputs, like Fuel Pump Status.

2. The second option is to use User Defined CAN Stream.
Below is an example how to send Fuel Pump (State). It transmits frame 512 decimal (0x200 hexadecimal).
512 is some example ID. It needs to match the one entered in PMU.

And then Create CANbus Mob and CANbus Input in the PMU:
Please note, that PMU uses hexadecimal CAN ID format 0x200, while ViPec uses decimal format 512.

[Sute]

Thanks for informative answer!

Just to clarify the ID number. For example, if I set ID as 500 in Vipec, PMU should have the ID as 0X500?

And under "Frame1" in Vipec I can list all the parameters that will be send to PMU? Or is "Frame" parameter for example for engine FAN that PMU recognizes from data stream?

[Jadzwin]

ID 500 in VIPEC is decimal number. 0X500 is hexadecimal.

You can use windows calculator to convert between radix.

So 500 is 0x1F4 hexadecimal

[Sute]

Getting forward with this.

Just to clarify. If I want to send TPS % info from Vipec to PMU (to start 2nd fuel pump as TPS over 20 %), I have now under parameters on ECU side in CAN-setting for transmitting TPS data/bits: "Start 2" and "Width 16" and divider 10 for TPS.

Is Bit setting "Start" in ECU side corresponding "Byte Offset" in PMU side? Or is it necessary to define this at all at PMU side? Bit Position on PMU side do not have same number as in ECU and changing Bit Position changes "Bit Count" that is probably the "Width" on ECU side?

And sending ECT info to PMU (to control FAN) bit start number in ECU side is 19 and width 16 bits.

It seems that start number in ECU means bit start number within the 64 bit frame.

So what are the settings in PMU side if I have set TPS in ECU as "Start 2" and "Width 16" and correspondingly ECT "Start 19" and "Width 16" ?

Thanks!

[jgm]

Hi,

Recently we've published PMU software 0.42 available at www.ecumaster.com/testVersions.html
It contains CAN stream for GenericDash2 in .CANX format (attached).
You can import it by using Add button in PMU ProjectTree, then Import .CANX file.
You only need to define proper CAN ID that matches the ECU CAN ID (we've already discussed it before).

There are two symbols c_ecu_tps and c_ecu_clt (for ECT).

[jgm]

Answering your question.
PMU uses ByteOffset 0..7, while Vi-Pec uses StartBit 0..63.

If you use Custom CAN stream in ECU it is recommended to use StartBit that is multiple of 8.

For example:
Vi-Pec PMU
StartBit=0 -> ByteOffset=0
StartBit=8 -> ByteOffset=1
StartBit=16 -> ByteOffset=2
StartBit=24 -> ByteOffset=3
StartBit=32 -> ByteOffset=4
StartBit=40 -> ByteOffset=5
StartBit=48 -> ByteOffset=6
StartBit=56 -> ByteOffset=7

The Size in the ECU corresponds to DataFormat in the PMU.
For example:
Size=16 in ECU -> "16 bit usinged" in PMU

[thokes82]

For example:
Vi-Pec PMU
StartBit=0 -> ByteOffset=0
StartBit=8 -> ByteOffset=1
StartBit=16 -> ByteOffset=2
StartBit=24 -> ByteOffset=3
StartBit=32 -> ByteOffset=4
StartBit=40 -> ByteOffset=5
StartBit=48 -> ByteOffset=6
StartBit=56 -> ByteOffset=7

Small mistake here... I think it is
StartBit=7 -> ByteOffset=1
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