ABS Hacking

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Re: ABS Hacking

Postby jlvaldez » Thu Jan 14, 2021 9:18 pm

Tazzi wrote:Passthrough basically removes the "send 1 receive 1" nature of the ELM protocol.

It allows all messages that meet the filter requirements to be sent to the computer instantly. You can still also send messages to the bus.



So i played with this tonight and it doesn't seem to work quite as I expect.

I
1) reset part
2) set protocol
3) set mask to 000000
4)turn off echo

I get packets passes through as long as there is no unaubmittes text in the terminal. For example, if I am typing the send message command out (but it's not being echoed back), i do not receive any messages until I press enter.

On top of that, it appears that all messages from first character entered to enter key are lost.

In reality, it's a low chance to lose a message with a program typing things out, but delays could cause issues here.

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Re: ABS Hacking

Postby Tazzi » Fri Jan 15, 2021 9:11 am

jlvaldez wrote:
Tazzi wrote:Passthrough basically removes the "send 1 receive 1" nature of the ELM protocol.

It allows all messages that meet the filter requirements to be sent to the computer instantly. You can still also send messages to the bus.



So i played with this tonight and it doesn't seem to work quite as I expect.

I
1) reset part
2) set protocol
3) set mask to 000000
4)turn off echo

I get packets passes through as long as there is no unaubmittes text in the terminal. For example, if I am typing the send message command out (but it's not being echoed back), i do not receive any messages until I press enter.

On top of that, it appears that all messages from first character entered to enter key are lost.

In reality, it's a low chance to lose a message with a program typing things out, but delays could cause issues here.


The 'echo' is the tool sending back each character as you send it. Depending on the terminal you are using, some send each character while you type, others only send it when you click a big button saying send.

For using terminal based stuff, you need echo on.
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Posts: 121
Joined: Mon Feb 11, 2019 12:48 pm
Location: DFW, Texas

Re: ABS Hacking

Postby jlvaldez » Mon Jan 18, 2021 4:01 am

I get it. I was using the terminal to test functionality as I wrote the code for software to do it.

While software would likely not spend much time sending the characters, it's possible that the OS puts the thread to sleep for a while to service other things. In this example, it looks like any incoming messages would be dropped, even with echo off?

I agree with Echo on, it makes sense to hold sending messages to the terminal until a command had been sent, but with echo off, I'd think it could happen at any point, no?

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