Search found 334 matches

by michael_l
Thu Jun 22, 2017 9:54 am
Forum: Projects
Topic: Need a circuit to detect when engine running from OBD2
Replies: 25
Views: 492

Re: Need a circuit to detect when engine running from OBD2

About the powering. I just got an idea that I could perhaps make it work with ATTiny85 i.e. DIP-8 version. It is a)very small to fit inside OBD2 connector case b) it has ADC and digital outputs c) it does not consume power like STM32. So I could make a small arduino program that monitors battery vol...
by michael_l
Thu Jun 22, 2017 9:50 am
Forum: Generic STM32F103
Topic: Error led pin working with BluePill ?
Replies: 6
Views: 171

Re: Error led pin working with BluePill ?

Did you try the Serial 2 error text output ? Re: 1 / 0 umm. Do you mean no crash at all, or an unhandled crash No, didn't try Serial2 yet. Based on the code it triggers only when an 'assert' fails. I mean no crash at all, I was expecting the processor to abort and stop because that's a division by ...
by michael_l
Sun Jun 18, 2017 5:21 pm
Forum: Generic STM32F103
Topic: Error led pin working with BluePill ?
Replies: 6
Views: 171

Re: Error led pin working with BluePill ?

Yes. I think its that function. BTW. There is also code to send a debug message about the error via the hardware serial, but I have never tested it, so I am not sure if it works. I think it may use Serial2 Yes, this works. It is kinda cool :-) I have blinking led with this line that results in "cra...
by michael_l
Thu Jun 15, 2017 11:31 am
Forum: Generic STM32F103
Topic: Error led pin working with BluePill ?
Replies: 6
Views: 171

Re: Error led pin working with BluePill ?

Yes, there seems to be a function in util.c 'throb' that gets called when abort occurs with a comment saying it fades the error LED on and off.

I'll report back after I've tested this.
by michael_l
Thu Jun 15, 2017 8:51 am
Forum: Generic STM32F103
Topic: Error led pin working with BluePill ?
Replies: 6
Views: 171

Error led pin working with BluePill ?

Seems error led pin works with Maple Mini. If my code crashed led starts the fade in/out loop. But this doesn't seem to work with Blue board. Any way to enable it ?
by michael_l
Fri Jun 09, 2017 10:47 am
Forum: Projects
Topic: Need a circuit to detect when engine running from OBD2
Replies: 25
Views: 492

Re: Need a circuit to detect when engine running from OBD2

Thanks for all the help. I did some more searching and found this one. This is basically what I want and need and it can handle about 200mA. Except that I'll have to reverse the logic so that it turns output HIGH when voltage is over some limit. This 555 most probably won't draw much current when it...
by michael_l
Wed Jun 07, 2017 2:39 pm
Forum: Projects
Topic: Need a circuit to detect when engine running from OBD2
Replies: 25
Views: 492

Re: Need a circuit to detect when engine running from OBD2

The device will be permanently attached to car. That's why the power consumption has to be minimized and I need an indication when the car is running.
Currently the wire that gets main power +12V will power the display from BP's 5V pin. So it's not enough to just put stm32 to sleep
by michael_l
Wed Jun 07, 2017 10:50 am
Forum: Projects
Topic: Need a circuit to detect when engine running from OBD2
Replies: 25
Views: 492

Re: Need a circuit to detect when engine running from OBD2

Actually I was thinking of digital data. But it looks like your BMW may output RPM on pin 9 of OBD 2 https://en.wikipedia.org/wiki/On-board_diagnostics#OBD-II But it looks like BMW only. In which case it should be fairly simply to trigger off that signal, either if its a pure analogue level or some...
by michael_l
Wed Jun 07, 2017 7:56 am
Forum: Projects
Topic: Need a circuit to detect when engine running from OBD2
Replies: 25
Views: 492

Re: Need a circuit to detect when engine running from OBD2

What car do you have ? Have you checked what OBD protocol it uses. I have an old Subaru, which seems to use a fairly standard protocol I'm not sure where all of these things are listed but mine appears to be listed here http://www.outilsobdfacile.com/vehicle-list-compatible-obd2/subaru and is compa...
by michael_l
Wed Jun 07, 2017 6:58 am
Forum: Projects
Topic: Need a circuit to detect when engine running from OBD2
Replies: 25
Views: 492

Re: Need a circuit to detect when engine running from OBD2

Yes. I was going to mention that the battery voltage normally drops very sharply when the starter motor is running. I've not checked my current car, but I remember some old cars I had the battery voltage dropped well below 10V when the starter was turning Of course the car may not start if you just...