Gm bcm and cluster can bus messages through eml327 script

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Gatecrasher
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Re: Gm bcm and cluster can bus messages through eml327 scrip

Post by Gatecrasher »

7E8 1013 5A90 xxxx Indicates this is the first frame in a multi frame message packet. 10 means it's the first frame, and 13 is the total number of bytes in hex. 17 digit VIN plus the two diag bytes = 19 (0x13)

Either your adapter needs to support automated flow control messages, or you need to handle that manually via Python. My OBDLink MX supports automated flow control. I've used it to write really long XML config strings to modules.

Good luck getting this stuff to print correctly with Python. I've just about given up trying to figure out how it calculates the cursor position.
kur4o
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Re: Gm bcm and cluster can bus messages through eml327 scrip

Post by kur4o »

https://www.scantool.net/scantool/downl ... tnterm.exe

Just get this little program from obdlink and test with it. It works great for obdlink and chinese crap adapters over bluetooth.
04colyZQ8
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Re: Gm bcm and cluster can bus messages through eml327 scrip

Post by 04colyZQ8 »

so it seems to kinda work ok in python if I print twice it will print the next line of vin read.

The strange thing is it is only working for pcm 7E8 is the response

OBDMX.write("AT SH 00 07 E0 \r\n")
OBDMX.write("AT CRA 00 00 07 E8 \r\n")

but when I change it to this for the bcm

OBDMX.write("AT SH 00 02 41 \r\n")
OBDMX.write("AT CRA 00 00 06 41 \r\n")

I still get all my responses from 7E8 WFT??? why if I do it in putty this works fine, idk why it won't work in python??

Yes the print is very frustrating in python
kur4o
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Re: Gm bcm and cluster can bus messages through eml327 scrip

Post by kur4o »

If you want to get rid of that elm problems and have a j2534 device,[ELm is not that good with CAN-too slow]

You can just use universal patcher for that and write some custom script and loops as much as you like, add as many filters as you like, so you don`t miss anything.

I can post some sample scripts to look at.
04colyZQ8
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Re: Gm bcm and cluster can bus messages through eml327 scrip

Post by 04colyZQ8 »

kur4o wrote:If you want to get rid of that elm problems and have a j2534 device,[ELm is not that good with CAN-too slow]

You can just use universal patcher for that and write some custom script and loops as much as you like, add as many filters as you like, so you don`t miss anything.

I can post some sample scripts to look at.
Yeah I mean I have mongoose pro j2534
And avt852

I tried universal patcher but it’s to complicated to use?

I just see 100s of messages scrolling so fast I can’t see what I send.
Tried to use the filter thing couldn’t figure it out!

I just want to see returns from bcm 06 41 or pcm 07 E8 and not both at the same time.

Also I want the other modules to shutoff lol! I tried to send a
Silent command but it didn’t work
ironduke
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Re: Gm bcm and cluster can bus messages through eml327 scrip

Post by ironduke »

If you turn the can formatting on you should get the multiline messages..

atcaf1 I beleive..
04colyZQ8
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Re: Gm bcm and cluster can bus messages through eml327 scrip

Post by 04colyZQ8 »

ironduke wrote:If you turn the can formatting on you should get the multiline messages..

atcaf1 I beleive..

Ok I’m getting multi line messages though I think I just call readline() again and the next line comes up, but why does it not change to 06 41 or 02 41 it’s stuck on 7E 8
ironduke
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Re: Gm bcm and cluster can bus messages through eml327 scrip

Post by ironduke »

04colyZQ8 wrote:
ironduke wrote:If you turn the can formatting on you should get the multiline messages..

atcaf1 I beleive..

Ok I’m getting multi line messages though I think I just call readline() again and the next line comes up, but why does it not change to 06 41 or 02 41 it’s stuck on 7E 8
Don't know the answer to that one, elms can be funny as they're all clones and some are better than others.

possibly not accepting the commands, are you looking for a response when you set the header?

I don't even remember using the cra command, just setting the header but back then I did just primarily talk to ecm's..

I have since upgraded to j2534 and c# and haven't used an elm in years, I got them to work but very problematic. still a newbie though, lol..

I think i'd try a reset and then set protocol and then set the header for the module you want to send messages to.. cra shouldn't be needed unless your using atma and want to filter specific messages.. If your sending and receiving you don't need it. Might need to reset it each time you change the header or cra command if it's not actually changing?
04colyZQ8
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Re: Gm bcm and cluster can bus messages through eml327 scrip

Post by 04colyZQ8 »

This is what I’m sending


AT Z
AT E1
AT L1
AT S0
AT AL
AT SP6
AT DP
AT AR
AT AT0
AT H1
AT SH 00 02 41
AT CRA 00 00 06 41

This works great in putty except I can’t seem to send larger commands
Like 3B xx xx xx xx xx xx xx xx xx xx xx xx xx
It says ? Instead Of ok j2534 sends this length np in dps

It’s likely possible with the elm327 I just don’t know what commands to type to send longer messages

The bigger issue is sending the above commands in python don’t work,
I get all my responses from 7e8 and they are correct which is very puzzling because that means it’s also sending to 07 EA which is the pcm. Yet I never write that to the eml327 anywhere in my python script

It’s like it’s ignoring the


AT SH 00 02 41
AT CRA 00 00 06 41

And going with a default setting?
But works in putty so I’m baffled
kur4o
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Joined: Sun Apr 10, 2016 9:20 pm

Re: Gm bcm and cluster can bus messages through eml327 scrip

Post by kur4o »

04colyZQ8 wrote:
kur4o wrote:If you want to get rid of that elm problems and have a j2534 device,[ELm is not that good with CAN-too slow]

You can just use universal patcher for that and write some custom script and loops as much as you like, add as many filters as you like, so you don`t miss anything.

I can post some sample scripts to look at.
Yeah I mean I have mongoose pro j2534
And avt852

I tried universal patcher but it’s to complicated to use?

I just see 100s of messages scrolling so fast I can’t see what I send.
Tried to use the filter thing couldn’t figure it out!

I just want to see returns from bcm 06 41 or pcm 07 E8 and not both at the same time.

Also I want the other modules to shutoff lol! I tried to send a
Silent command but it didn’t work

I can set you some test files that will log only nodes 7e8 and 641, You can send whatever you like and only responses from those will be printed
Do you want to manually send data or automated. Give me some examples what needs to be set and at what interval. You can do all kind of funny things like make modules quiet, unlock them change vin or other data, Even you can dump a module using mode23 or 35 commands.

I suspect you have opened raw CAN, vs iso15675 protocol, In raw CAN you have to add bytes count and padd the message to full 12 bytes

For example in raw CAN this frame
00 00 07 e0 02 1a 90 00 00 00 00 00 [THIS is what is send on bus]
equals this in iso15675
00 00 07 e0 1a 90[this is what is send to tool]
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