88 Toyota Camry 2.0 (3SFE)

What engine are you torturing? Is it inside some car?
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Re: 88 Toyota Camry 2.0 (3SFE)

Post by theflyingdutchp » Tue Jul 12, 2016 12:01 am

kb1gtt wrote:Correct, wattage is low, that's a large part of how you determine what you are looking for. After that you try to look for as much change in the area you are normally operating at. Keep in mind you can use 2 resistors in series, you don't have to buy it in one resistor.
Gotcha, just wanted to make sure we were gonna blow an input pin - looks like we are good to Vdd + .03V? Good point on the series (or parallel I suppose). If I'm not getting good resolution with the 3.3k I'll do that.
russian wrote:
theflyingdutchp wrote:Still need to confirm with a real world reading and log the AFM.
Noone likes vane door and real world reading is often hard to come by, that's how a lot of people choose to use known MAP sensors and speed density algo since the conversion is so easy.
Yea I'm not too excited about the vane door either. If I can make it work I'll just run with it, I came across a MAF table correction guide the other day that was pretty step-by-step. Otherwise I've got a Ford MAF laying around(and a start on a table for it) - although I'm not sure it will have good resolution now that I think about it. (4.6L MAF on a 2.0L :D) Not afraid of a J/Y trip for parts but I'd prefer to run mostly stock sensors.

EDIT: Parts order placed 8-)

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Re: 88 Toyota Camry 2.0 (3SFE)

Post by theflyingdutchp » Sun Jul 24, 2016 11:56 pm

Dangerously hot in California today. Hiding inside so I did some datalogging on the AFM. Looks like a nice simple trimpot.
Still need to write the last bit of code for the toaster reflow, then I'll try it out tonight when it cools down.

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Re: 88 Toyota Camry 2.0 (3SFE)

Post by theflyingdutchp » Thu Sep 13, 2018 5:01 am

A blast from the past!
So I finally (2years+ really?!....) got my reflow oven working...

I'm probably going to wait until next week until I start prepping to/reflowing the PCB (I'll be out of town this weekend).
In the meantime I've got to read through y'alls advice again, calculate my pullups/downs, and probably log the TPS and AFM once more.

To anyone who is considering reflowing their own ECU who hasn't reflowed before. Don't bother - your project scope is going to BALLOON - just save another few weeks worth of pay and years of your own time and buy the complete board. I'm still not done...

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Re: 88 Toyota Camry 2.0 (3SFE)

Post by theflyingdutchp » Wed Sep 19, 2018 6:25 am

Ok - I printed out the schematic of the stock ECU connections to organize my work. I think I've got most everything sorted. If someone has a moment to answer some questions that'd be great!

Water temp sensor. If I choose a dividing resistor (not sure what its official name is) of 2500ohms I get a power dissipation of ~2mW. However, the voltage difference between 100 and 120 degrees Celsius is then ~0.08V. Will this be sufficiently large? I can provide a plot of the prediction response if its helpful.

ISC - As previously discussed its a two-pin output PWM. The second pin essentially is the remainder - IE: if PIN1 is at 40%, PIN2 is at 60%. Would it be possible to get this functionality in software or would it be easier to build some kind of high-speed switching hardware in the proto area?

VR sensor - Should I be concerned with this page on the wiki? Or should I just set the circuitry up as shown here? It appears that the trigger pattern is already supported (Honda 4 + 24) - but I'll confirm the tooth timing. The two wheels share a common ground - would it be better to disconnect/remove one of the sensors?

Igniter driver - I'm fairly certain this is a low-amperage output. If I'm wrong, will the rusefi hardware be damaged? I'm guessing that I simply won't get spark/I'll get a weak spark - but I'd like a second opinion before I try it! I've included the OEM schematic below. IGT goes hi to charge the coil, and low to fire. IGF is a fire confirmation signal - it mimics the pulse through the plug. I've found some other documentation that refers to a power transistor inside the igniter.

Ignition schematic:
Image

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Re: 88 Toyota Camry 2.0 (3SFE)

Post by kb1gtt » Wed Sep 19, 2018 10:31 am

On page 3, it shows the IAT and CLT with a 2700 k ohm resistor pulled up to 5V. The 2700, is because several thermistors need less than 2mW of dissipated energy. The 2700 has worked well and I'd suggest it be used.

I believe we have some good reports of using your setup as shown here. So you should be OK if you are not paranoid about the intricate details noted on the VR page. The OEM sensors have already considered those bits of information.

I expect the HI/LO driver can drive 0.125A at the max ambient temperature of 85C (185F). If you consume more than 0.125A and if you are at this elevated temperature, then the chip will go into thermal shut down, and you will fail to spark. Other than this performance issue, I do not expect any other issues. The TC4427 can technically drive something like 2A. However the thermal resistance of the particular package makes it un-likely for you to get that much current in a long term steady state situation. If your ignition is the one I'm thinking of, which was common on many Honda's for a long number of years, you'll be fine with driving it with the HI/LO driver.

I'm not sure about the ISC. It might be good to re-discuss. I believe the FSIO can do this, but I'm not connecting all the dots.
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Re: 88 Toyota Camry 2.0 (3SFE)

Post by russian » Wed Sep 19, 2018 10:33 am

theflyingdutchp wrote:
Wed Sep 19, 2018 6:25 am
ISC - As previously discussed its a two-pin output PWM. The second pin essentially is the remainder - IE: if PIN1 is at 40%, PIN2 is at 60%. Would it be possible to get this functionality in software or would it be easier to build some kind of high-speed switching hardware in the proto area?
So is the second output always a logical not of the first output?
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Re: 88 Toyota Camry 2.0 (3SFE)

Post by theflyingdutchp » Wed Sep 19, 2018 4:06 pm

kb1gtt wrote:
Wed Sep 19, 2018 10:31 am
..
With the service manual resistance ranges I get a curve like this using a 2700k resistor. However - power dissipation is 2.31mW using 5V.
Image
If I use a 3300K with 5V I get a dissipation of 2mW but obviously the curve flattens. In the spreadsheet you linked absolutely ages ago (sorry) I believe you had used 4.5V - is this more realistic?
Also, if the AFM or TPS don't give good voltage ranges should I spec out dividers for those as well?

VR - I think Nippon-Denso or another Japanese manufacturer designed these ignition systems - I've seen similar IGT/IGF/G/NE signal/trigger setups on Hondas, Toyotas, and Mazdas. I wouldn't be surprised if Mitusbishi and Nissan had them as well. Anyway, thanks for the details on the current limitations!
russian wrote:
Wed Sep 19, 2018 10:33 am
So is the second output always a logical not of the first output?
That's a really good way to describe it! I suppose the PWM would be slightly out of phase but thats not a problem. Just so we're clear:
Pin 1 | Pin 2
100% - 0%
60% - 40%
40% - 60%
0% - 100%
Last edited by theflyingdutchp on Wed Sep 19, 2018 4:11 pm, edited 1 time in total.

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Re: 88 Toyota Camry 2.0 (3SFE)

Post by russian » Wed Sep 19, 2018 4:11 pm

How hard would it be to implement this custom second inverted signal in hardware? Would prefer to avoid this in the firmware.
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Re: 88 Toyota Camry 2.0 (3SFE)

Post by theflyingdutchp » Wed Sep 19, 2018 4:14 pm

russian wrote:
Wed Sep 19, 2018 4:11 pm
How hard would it be to implement this custom second inverted signal in hardware? Would prefer to avoid this in the firmware.
I can take a crack at putting a circuit together, but it'd be great if yall could provide some feedback on a schematic at some point. What is the frequency that the PWM operates at?
EDIT: Nevermind, I see that the frequency is configurable.
Image

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Re: 88 Toyota Camry 2.0 (3SFE)

Post by kb1gtt » Thu Sep 20, 2018 12:58 am

theflyingdutchp wrote:
Wed Sep 19, 2018 4:06 pm
In the spreadsheet you linked absolutely ages ago
No worries. I notice this morning or yesterday that apparently the original shared spread sheet needed to be "published" and not just shared. Once it was published, the shared link showed up much better in the forums. It appears that if you just share it, then people can download it, but the auto-magic forum tools which generate a preview, those don't work. Any how, it's now more obvious.

What is the manuals claimed ohms vs temperature? Keep in mind that flat at the low end isn't really much of a problem. AKA 0C and 10C basically have the same priming pulses and spark advance. It's also not super critical at the hotter temperatures either 90C and 100C also basically have the same compensations. Your fuel pulses vary just a little bit if you are off by 10C. However the ECU needs to enrich fuel when cold, and not when hot.
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Re: 88 Toyota Camry 2.0 (3SFE)

Post by theflyingdutchp » Thu Sep 20, 2018 5:17 am

kb1gtt wrote:
Thu Sep 20, 2018 12:58 am
..spread sheet...
I think something must have changed - I downloaded it previously.
In any case, I've noticed you're using 4.5V instead of 5V. Is this more realistic?
kb1gtt wrote:
Thu Sep 20, 2018 12:58 am
What is the manuals claimed ohms vs temperature? Keep in mind that flat at the low end isn't really much of a problem. AKA 0C and 10C basically have the same priming pulses and spark advance. It's also not super critical at the hotter temperatures either 90C and 100C also basically have the same compensations. Your fuel pulses vary just a little bit if you are off by 10C. However the ECU needs to enrich fuel when cold, and not when hot.
Thanks for the use-case clarification on the temperature info!
For both the WTA/CLT and IAT the manual claims:
Temperature(C) | Resistance Range(kOhm)
-20...................| 10-20
0.....................| 4-7
20...................| 2-3
40...................| 0.9-1.3
60...................| 0.4 - 0.7 (IAT ends here)
80...................| 0.2-0.4
100.................| 0.15-0.2
120.................| 0.9-0.1

-ISC-
An inverting gate on the logic side of one of the TC4427s seems easiest. I noticed none of the pins at the STM have through holes to pull a wire to the proto area.
Can I use PE1 instead? I've made a crude drawing of what I'm thinking.
Obviously I still need to pick hardware - I'm aiming for a small package to not take up too much space, plus a quick response time, and correct logic level. Any other things to consider hardware wise?
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Re: 88 Toyota Camry 2.0 (3SFE)

Post by kb1gtt » Thu Sep 20, 2018 10:19 am

I see your sensor like this.

https://docs.google.com/spreadsheets/d/ ... sp=sharing

Take note that when the voltage received at the harness connector is 3V, the sensors tolerance will read between -4C and +10C. I also recall the ADC being something like 12bit, so 3V / 4095 = 0.7mV as the minimum detectable voltage increment. I see the difference between 250mV @ 100C and 140mV @ 120C. So you should have good detectable resolution at the high end as well as the low end. AKA the flatness is not a bid deal. The big deal is that at 120C you'll see 90mV to 100mV. At the ADC that's 45mV and 50mV. There's nearly 5 ADC increments caused just by the sensor tolerance. So the ADC shouldn't be a significant source of error in this circuit.

Also keep in mind that 3V is scaled down at the brain chip. So the STM32 chip see's 1.5V not 3V. This is because the ADC's max input is 3V not 5V.

Oh, also I think it's 0.09V not 0.9V for the 120C reading.
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Re: 88 Toyota Camry 2.0 (3SFE)

Post by theflyingdutchp » Fri Sep 21, 2018 8:34 pm

kb1gtt wrote:
Thu Sep 20, 2018 10:19 am
I see your sensor like this.
..

Take note that when the voltage received at the harness connector is 3V, the sensors tolerance will read between -4C and +10C. I also recall the ADC being something like 12bit, so 3V / 4095 = 0.7mV as the minimum detectable voltage increment. I see the difference between 250mV @ 100C and 140mV @ 120C. So you should have good detectable resolution at the high end as well as the low end. AKA the flatness is not a bid deal. The big deal is that at 120C you'll see 90mV to 100mV. At the ADC that's 45mV and 50mV. There's nearly 5 ADC increments caused just by the sensor tolerance. So the ADC shouldn't be a significant source of error in this circuit.

Also keep in mind that 3V is scaled down at the brain chip. So the STM32 chip see's 1.5V not 3V. This is because the ADC's max input is 3V not 5V.
Ok, looks good then, thanks! I'll check each sensor manually before I run the thing - that should minimize any tolerance induced issues.
kb1gtt wrote:
Thu Sep 20, 2018 10:19 am
Oh, also I think it's 0.09V not 0.9V for the 120C reading.
Ooops :oops:

I've got an ISC circuit in mind - I'm not sure if this is your area of expertise kb1gtt? But if someone could give me some input that'd be great. I'm still very new to this.
Image
Chip is a TI CD40107BE. Its a NAND gate but its a smaller package than the NOT gates I could find on Digikey. Response time is in the 100s of nanoseconds - plenty fast.
Should I include a cap between the 5V and ground for noise filtering?
I figured I'd remove the headers STM side to disconnect PC7 and PC9.

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Re: 88 Toyota Camry 2.0 (3SFE)

Post by kb1gtt » Sat Sep 22, 2018 12:04 am

I'm still ignorant about ISC or why you need the inverted signal, so I'm not sure if the signal would work or not. That said....

Yes a 0.1uF or similar small decoupling cap is a good idea. It's probably not critically, but doesn't hurt. The theory is that sharp edges of the digital signal use lots of high frequency bandwidth. If you have local energy in a cap, that energy will come from the cap instead of the cap which is far away. AKA your antenna to the local cap is much smaller, than your antenna if you pull from a far away cap. By shortening the antenna, you minimize both how much RF you emit, as well you get more crisp square edges. So yes a decoupling cap is a good idea. However the PCB has a fair bit of capacitance, so it's probably not critical.
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Re: 88 Toyota Camry 2.0 (3SFE)

Post by theflyingdutchp » Sat Sep 22, 2018 3:11 am

kb1gtt wrote:
Sat Sep 22, 2018 12:04 am
I'm still ignorant about ISC or why you need the inverted signal, so I'm not sure if the signal would work or not. That said....
In case you're curious, I've included some excerpts from the Toyota documentation I've been able to find.
The Idle Air Control (or Idle Stability Control, from now on IAC or ISC) system bypasses air around the throttle butterfly to control the idle speed and provide high idle during warm up and under high electrical load. Interestingly, the powersteering and airconditioning have their own mechanical bypass systems... Anyway..
The issue is that the ISC/IAC Valve is neither fully closed nor fully open in the 'neutral' (IE: no power applied) position. Opening and closing the valve relative to the neutral position requires two signals.

I can tweak the actuator farther towards the closed postion by loosening the screws, rotating it, and then tightening them back down - but it's not fully closed.

I suppose I could just try to run it as is. If the warm idle is too high due to high airflow then I'll have to come up with a solution. Another option is to see if a newer-model actuator will swap over. The Toyota docs mentioned a 'single driver rotary IACV.' I've got to go to the junkyard to get an automatic model Throttle Position Sensor so I'll look around while I'm there.

Anyway, here are the manual excerpts covering the system...
Image
Note that the OE system provides a constant +12V to the actuator and grounds through the ECU. I've tested the unit - it works the other way as well (grounding the +12V terminal and modulating the applied voltage).
Image
Don't worry about the bimetallic strip - there is a backup mechanical system in case the electrical control/actuation system fails.
Image
kb1gtt wrote:
Sat Sep 22, 2018 12:04 am
Yes a 0.1uF or similar small decoupling cap is a good idea. It's probably not critically, but doesn't hurt. The theory is that sharp edges of the digital signal use lots of high frequency bandwidth. If you have local energy in a cap, that energy will come from the cap instead of the cap which is far away. AKA your antenna to the local cap is much smaller, than your antenna if you pull from a far away cap. By shortening the antenna, you minimize both how much RF you emit, as well you get more crisp square edges. So yes a decoupling cap is a good idea. However the PCB has a fair bit of capacitance, so it's probably not critical.
10-4. Thanks for the explanantion! If I understand correctly, the capacitors act as a sort of a buffer during the High-Low transition?

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Re: 88 Toyota Camry 2.0 (3SFE)

Post by kb1gtt » Sat Sep 22, 2018 9:56 am

Ah, I understand Toyota's ISC is my IAC. I should have put that in google translate earlier and specified to translate from Toyata --> kb1gtt speak.

Good thing you posted those snippets. The HI/LO driver will not work, it does not drive enough amps, and it doesn't have the inductive clamping you would need. You can do this with some of the same drivers you're using for the injectors. Do you have 2 of those to spare? If so then I see 2 possible solutions using those drivers.

-- Solution 1, Do it in software. The timing of this is not critical. Perhaps @ can comment about if FSIO can simply read a channel and invert it. AKA set your IAC settings to PWM and tell it to control the pin for the North coil. Then set FSIO to read the north coil, invert it and send it to the south coil. I think that's an option, but @ would know better. The small amounts of jitter caused by software should be of little importance.

-- Solution 2, set one of the STM32's output to high impedance, such that it does not drive the output. Then use your circuit to invert and drive the other channel, via something like P20, found on page 1.

Also if you have these injector channels, there is likely a benefit of installing the flyback diodes on these channels. The injector drivers with their over voltage protection circuit, will be a bit more abrupt in how it sends the open and closed pulses. Which will likely make noise or perhaps be noticed in the ability to control the valve. If you install the flyback diodes, it will likely smooth out the valves reaction, removing noise and becoming a bit better to control. You can install this diode after you have it mostly running. Just make note you may look to install a diode like D14, or D23.
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Re: 88 Toyota Camry 2.0 (3SFE)

Post by theflyingdutchp » Mon Sep 24, 2018 4:35 am

russian wrote:
Wed Sep 19, 2018 4:11 pm
How hard would it be to implement this custom second inverted signal in hardware? Would prefer to avoid this in the firmware.
I think he'd prefer it to be done in hardware. Hopefully that gives him some time to work on more exciting features.
I have plenty of extra low-side driver space. It's batch injection (so two), plus the two for ISC/IAC, thats four out of twelve for Frankenso.

Copy that on the flyback diodes - I'll add them to the list. I imagine I should install them on the injector circuits as well?

I was hoping to get more done this weekend but I'm coming down with a cold :/ Hopefully I can find some time to head to the J/Y for those parts this week. Other than the ISC hardware I think its all set now. I need to spend an evening or two going through the needed hardware, what I have, etc, and then on to reflow soldering. At my pace it will probably be a few weeks :roll:

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Re: 88 Toyota Camry 2.0 (3SFE)

Post by kb1gtt » Mon Sep 24, 2018 9:18 am

For now I'd say pick 2X low side drivers and wire them. You could even setup the North coil to work. Then once several other things are working and idle is your problem, then we can deal with the inverted signal.
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Re: 88 Toyota Camry 2.0 (3SFE)

Post by theflyingdutchp » Wed Sep 26, 2018 8:55 pm

kb1gtt wrote:
Mon Sep 24, 2018 9:18 am
For now I'd say pick 2X low side drivers and wire them. You could even setup the North coil to work. Then once several other things are working and idle is your problem, then we can deal with the inverted signal.
Fair enough. I think I've got all the details sorted out.

Is this the correct discovery board?

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Re: 88 Toyota Camry 2.0 (3SFE)

Post by kb1gtt » Wed Sep 26, 2018 9:10 pm

I believe so, it looks about right. You may need to flash the latest firmware when you get it. Other than that it looks right to me.
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Re: 88 Toyota Camry 2.0 (3SFE)

Post by theflyingdutchp » Sun Sep 30, 2018 6:45 am

Ok, I did an inventory of the components I have on hand.

I assume D1001 = D1 in the tindie kit?
Likewise D1004 = D4?
And D1002 and D1003 = '#25 x2 thru-hole diode'?

Got a few remaining capacitors and resistors on the way, plus the STM32...

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Re: 88 Toyota Camry 2.0 (3SFE)

Post by kb1gtt » Sun Sep 30, 2018 9:43 am

D1 to D4 should be a LED's found on the STM32 brain page.
D1.png
D1.png (3.71 KiB) Viewed 1411 times

D100# are part of the power supply.
PS.png
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Re: 88 Toyota Camry 2.0 (3SFE)

Post by russian » Sun Sep 30, 2018 12:56 pm

theflyingdutchp wrote:
Sun Sep 30, 2018 6:45 am
Ok, I did an inventory of the components I have on hand.

I assume D1001 = D1 in the tindie kit?
Likewise D1004 = D4?
And D1002 and D1003 = '#25 x2 thru-hole diode'?
I think so. I recommend zooming in at https://rusefi.com/images/Frankenso/ - a few large components are only found in one place
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Re: 88 Toyota Camry 2.0 (3SFE)

Post by theflyingdutchp » Thu Oct 04, 2018 9:44 pm

russian wrote:
Sun Sep 30, 2018 12:56 pm
I think so. I recommend zooming in at https://rusefi.com/images/Frankenso/ - a few large components are only found in one place
Agreed, its the smaller ones I wasn't sure about, but if D1 = D1001 and D4 = D1004 then I think its safe to assume D2 & D3 = 1002, 1003.

kg1gtt - I should have been more specific. The tindie kit came with some parts in baggies with little pieces of paper with 'D1', 'D4', etc printed on them.

Anyway, still waiting on parts... In other news, I'm taking an assembly language class at the moment, so I'm converging on C from above (Python, C++ type languages), and below hahah :D Maybe at some point I could write some simple modules... Is there a good place to start reading about how I might get started on this (specific to rusEfi?)

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Re: 88 Toyota Camry 2.0 (3SFE)

Post by russian » Fri Oct 05, 2018 12:12 am

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Re: 88 Toyota Camry 2.0 (3SFE)

Post by Thommm » Fri Oct 05, 2018 1:09 pm

By far the easiest way to invert a signal is by using a buffer transistor. Since you only need to control the input of the TC4427 you could use a tiny small signal MOSFET/BJT with a pull-up on the drain/collector like in the below schematic:
main-qimg-d49bd7ccd25f9fd159be7c8a3dbc5a34.png
main-qimg-d49bd7ccd25f9fd159be7c8a3dbc5a34.png (17.4 KiB) Viewed 1342 times
No need for a power supply, pure simpleness :D

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Re: 88 Toyota Camry 2.0 (3SFE)

Post by theflyingdutchp » Fri Oct 19, 2018 7:17 am

I'm not dead! Sorry for being silent y'all. School is picking up again and I've been interviewing for internship positions for the summer.
russian wrote:
Fri Oct 05, 2018 12:12 am
All we have is https://rusefi.com/docs/html/ and viewtopic.php?f=5&t=10
Better than nothing!

Thommm wrote:
Fri Oct 05, 2018 1:09 pm
By far the easiest way to invert a signal is by using a buffer transistor. Since you only need to control the input of the TC4427 you could use a tiny small signal MOSFET/BJT with a pull-up on the drain/collector like in the below schematic:
main-qimg-d49bd7ccd25f9fd159be7c8a3dbc5a34.png
No need for a power supply, pure simpleness :D
Hey thanks! That will probably be easier to hack in, err I mean, install. It's been a while since I've covered MOSFETs, so please correct me if I'm wrong, but I'd attach my STM output to the G lead and then my second TC4427 input to the D lead? Goes hi when G is lo, lo when G is hi because the MOSFET sinks the current to ground?

In other news, I bought a TPS from an automatic Toyota from the same era. Its a four wire with a proper varistor position sensing. Looks to be bolt on, but not plug compatible unfortunately. Nothing too complicated to fix. Unfortunately I wasn't able to find a simpler ISC/IAC valve.

theflyingdutchp
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Re: 88 Toyota Camry 2.0 (3SFE)

Post by theflyingdutchp » Tue Nov 13, 2018 12:03 am

Well I pasted and flowed what I could of the ECU over the weekend. I'm missing a few resistors and capacitors so I've got to order those. Also had an issue with the solder oven thermistor pushing one of the power supply capacitors off it's pads. I think I'll end up fixing all of that with a hot-air rework station and maybe borrow a friend's microscope to check some of the joints.

For anybody reading this considering doing it themselves. Unless you've got a reflow oven already I wouldn't bother. Price in the cost to make a solder mask too.

Anyway, here are some pics.
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kb1gtt
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Re: 88 Toyota Camry 2.0 (3SFE)

Post by kb1gtt » Tue Nov 13, 2018 11:47 am

A low cost reflow oven can be made out of a toaster oven, like a black and decker Infrawave. However I agree, populating it yourself is not cost effective. Your best off getting a populated board. There is allot of work that goes into populating this board, and allot of very small steps which can cause it to fail. One badly installed $0.001 resistor can destroy the entire thing.
Welcome to the friendlier side of internet crazy :)

theflyingdutchp
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Re: 88 Toyota Camry 2.0 (3SFE)

Post by theflyingdutchp » Mon Nov 19, 2018 7:27 pm

Yea that is exactly what I did. I probably spent more time than was necessary figuring it all out, and it was a good learning experience. But yea, not worth the hassle. Especially because its still not done and I definitely need to check some of the finer pitch chips for bridging.

Anyway, I'm out of town for the next week or so - the rest of the components came in before I left so I'll try to get that soldered when I'm back in town. Turns out a friend of mine has a hot-air rework station I can use so that's the plan.

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