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Re: no gear changes..stays in first.VSS ISSUE.Thoughts pleas

Posted: Sat Jul 05, 2014 6:37 pm
by zen
question..
i have wired up gpio as 4l60..ie using sol3 driver transistor..as i dont have a sol3 i have just left it floating and not connected processor jumper to gpio board..

will this cause sol3 trasistor to go into oscillation etc??

i dont see that it will, but now (at 3.30am) wondering??

also going to try lm2907 crt again. but with out optocoupler, prehaps as frequency doubler variable inductance transducer crt, but with vss trigger wheel tooth count halved..??but this time jumping gpio vr1 crt out, ie straight to processor pto pin on 25 way header..(ensuring max voltage of 5v though)

wondering if i will get any sleep today..lol

Re: no gear changes..stays in first.VSS ISSUE.Thoughts pleas

Posted: Sun Jul 06, 2014 5:18 am
by zen
ok..it might now be working....

i have kept the lm2907 crt..dumped the optocoupler and used the crt from datasheet..ie 1 pulse in 1 pulse out.
i have put a 10k preset as potential divider on output and 0.1uf to gnd
this goes directly to pt0..via a wire..i will alter gpio crt later to use ampseal plug.
without 0.1u it still goes at44mph at zero but is ok once moving..scoped the vss out of lm2907 and there is massive high frequency noise..its being picked up from car, but no idea where..

i think a 5.1v zenor across output would be a good idea to protect cpu, but concerned about the noise it may generate..

so far road tested to 30mph...cant test higher as in town..

please can someone explain to me masking...i have set to 10..at 85 was useless..thank you