Problem: sometimes computer just does not recognize sequencer when powered on. it's as if it's not even plugged into serial connection, although sequencer seems to be functioning while comms won't work.
initial configuring on the bench for my Pontiac, i never had the problem. when wired into that car, i had this problem intermittently.
Kris said in his posts that he is having same problem on his car, but his sounded worse.
now, i have wired sequencer to a donor L-Jet box for BMW, and configuring on the bench. sometimes comms works, sometimes not, but makes it impossible to work.
i don't know how to test for this problem, and the fact that it's intermittent won't help matters any. but, for debugging purposes, it's helpful to know that it's not isolated to my situation.
suggestions on identifying / solving problem?
Comms Problem
Moderators: grippo, grippo2, Bruce Bowling
Forum rules
Read the manual to see if your question is answered there before posting. If you have questions about MS1/Extra or MS2/Extra or other non-B&G code configuration or tuning, please post them at http://www.msextra.com The full forum rules are here: Forum Rules, be sure to read them all regularly.
Read the manual to see if your question is answered there before posting. If you have questions about MS1/Extra or MS2/Extra or other non-B&G code configuration or tuning, please post them at http://www.msextra.com The full forum rules are here: Forum Rules, be sure to read them all regularly.
"A Clue"
anyone with kids that watches 'Dora The Explorer' can hear her voice say: "a clue"....
anyway....
i found that if i just keep cycling power, it eventually will connect.
something that Kris reported about bootloaders not being tied in. i pared down wire connections to only 12v and ground to JimStim.
repeated cycling of power to unit:
with bootloaders tied, connects about 80-90% of the time.
with bootloaders untied, connects 10-20% of the time.
and then, those frequencies will vary just circumstantially.... sometimes it's worse, sometimes it's better.
anyway....
i found that if i just keep cycling power, it eventually will connect.
something that Kris reported about bootloaders not being tied in. i pared down wire connections to only 12v and ground to JimStim.
repeated cycling of power to unit:
with bootloaders tied, connects about 80-90% of the time.
with bootloaders untied, connects 10-20% of the time.
and then, those frequencies will vary just circumstantially.... sometimes it's worse, sometimes it's better.
-
racingmini_mtl
- Helpful Squirter
- Posts: 61
- Joined: Sun May 02, 2004 5:51 am
- Location: Montreal, Canada
Re: Comms Problem
Does it do the same thing if you power up the sequencer without the cable connected and then connect it?
Jean
Jean
Re: Comms Problem
i'm thinking this must be related to the ignition problems since ignition pulses come from 5v also. the whole VREF thing is very peculiar.
as per Bruce, on why bootloaders get tied to VREF on beta units: "for the beta units this is correct. Both processor lack the series resistance that keep noise from damaging the processor, its the only line not protected with resistance. We learned this the hard way with early Microsquirts but the sequencer was already in PCB stage before we figured it out. Hooking them to Vref keeps them happy, and the ports are inputs and no real appreciable current flows. But if there are P/S unregulation situations I could see this adding to the resets."
ca434sbc4 was going to pull the bootloader wires and put a pullup to these, i wonder if this is the answer.
as per Bruce, on why bootloaders get tied to VREF on beta units: "for the beta units this is correct. Both processor lack the series resistance that keep noise from damaging the processor, its the only line not protected with resistance. We learned this the hard way with early Microsquirts but the sequencer was already in PCB stage before we figured it out. Hooking them to Vref keeps them happy, and the ports are inputs and no real appreciable current flows. But if there are P/S unregulation situations I could see this adding to the resets."
ca434sbc4 was going to pull the bootloader wires and put a pullup to these, i wonder if this is the answer.
Re: Comms Problem
sometimes it just won't connect at all. the comms problem is more erratic than the frequencies i estimated above (either with or without bootloaders tied to VREF).
i've been trying to read up a bit on open gates and pullup resistors. it looks like tying it to VREF should keep the voltage from floating at the gate, but VREF seems to be where noise has been introduced previously for me. i like the idea of the new schematics where bootloaders are pulled up to VCC. i'd like to try this bootloader mod that Marc was talking about.
surface mount is obviously very difficult to mod, but i think it can be done using headers.
on bottom of board, where ampseal is soldered through board, can i solder a wire from each bootloader pin, through a 10k resistor, and wire it to pin 3 of J4 (VCC)?
i've been trying to read up a bit on open gates and pullup resistors. it looks like tying it to VREF should keep the voltage from floating at the gate, but VREF seems to be where noise has been introduced previously for me. i like the idea of the new schematics where bootloaders are pulled up to VCC. i'd like to try this bootloader mod that Marc was talking about.
surface mount is obviously very difficult to mod, but i think it can be done using headers.
on bottom of board, where ampseal is soldered through board, can i solder a wire from each bootloader pin, through a 10k resistor, and wire it to pin 3 of J4 (VCC)?
Re: Comms Problem
solved.
ended up being a bad cable with intermittent connection. made it particularly difficult to diagnose because as it was intermittent, the board went bad, and all the pulling out the back of laptop messed up the connection i think. anyhow, another board and fixed cable sends me on my way.
ended up being a bad cable with intermittent connection. made it particularly difficult to diagnose because as it was intermittent, the board went bad, and all the pulling out the back of laptop messed up the connection i think. anyhow, another board and fixed cable sends me on my way.