by Merp » Mon Mar 02, 2009 4:30 pm
Bump!
I'm having some issues with my SHbootmode setup.
To check the wds from the 555 timer, I was hooking up a headphone with a large resistor, and comparing it to a test tone. Just to be sure, I hooked it up to a scope, and it's coming in around 150hz, not 125hz, as a square wave between 0V and 2V (crossing the 1.5v TTL threshold), this is based on the scope's calibration port.
I found a 555 timer equation and plugged in the schematic, giving 145.8hz, so I'm pretty sure the wds is good enough.
I used the same setup to tap into the send and receive lines of the circuit, and I get an intermittent click whenever ECUflash is sending the boot command (constant TTL high with a low signal every second or so), but nothing on the response line, which matches the logs 'no bit rate adjust response'.
So, either i'm not powering on the ecu properly, or the wds is off too far. I'm leaning towards the former, specifically the order of doing things. I've tried powering the 5V then 12V, 12V then 5V, doing everything fast, and slow, to no avail.
Forgot to mention, I'm also running a ground wire between the ecu and usb circuit grounds. (engine ground pin to the pad grounded by the circuit).
I've tried using a battery @ 12.5V and an adapter at 12V, so I don't think low voltage is an issue getting the ecu powered up. I'm using every pin I can find listed for 12V or ground in the manual. (constant 12V, starter 12V, and 5 different ground pins, all triple checked)
Also, another issue that comes to mind is the pad numbers, I'm working on an A8DH200X (22611AL350) ECU, and using the pad numbers provided in the schematic.
Any suggestions on the startup sequence?
Thanks.