From Diy_Efi-Owner Fri May 6 02:43:50 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA08838; Fri, 6 May 94 02:43:50 GMT Received: from dopey.cc.utexas.edu by coulomb.eng.ohio-state.edu via SMTP (920330.SGI/920502.SGI) for /usr/local/mail/majordomo/wrapper resend -p bulk -M 10000 -l Diy_Efi -f Diy_Efi-Owner -h coulomb.eng.ohio-state.edu -s -r DIY_EFI@coulomb.eng.ohio-state.edu diy_efi-outgoing id AA08832; Thu, 5 May 94 22:43:48 -0400 Received: (from efrank@localhost) by dopey.cc.utexas.edu (8.6.8.1/8.6.6/cc-wf-sunos.mc-1.1) id VAA21894; Thu, 5 May 1994 21:43:39 -0500 Date: Thu, 5 May 1994 21:43:37 -0500 (CDT) From: The_Mechanic Subject: Re: Some thoughts and questions on EFI To: DIY_EFI Cc: DIY_EFI In-Reply-To: <940505144423.2dc04180@STDVAX.GSFC.NASA.GOV> Message-Id: Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: Diy_Efi-Owner Precedence: bulk Reply-To: DIY_EFI@coulomb.eng.ohio-state.edu This is great. Perhaps we should all set up some sort of "standards" or at least a list of reference measurements like Dirk listed below? This way, all work would be complimentary and mutually beneficial. A couple of quick questions (from an electronics-ignorant ME type guy): - the 68HC11 microcontroller chip is an 8 bit unit, right? Is there a similiar chip available in a 16 bit architecture? Would it even be nescessary? - it would be great to develop a system with some accompanying software so that a laptop PC could interface "Real time" with the engine computer. Adjustments could be made "on the fly" with the engine running. This would be wonderful on the dyno. Also, an interface that would port information over to the Superflow SF-901 software would also be real cool. Are these out of reach? I think its already time for some sort off FAQ/STANDARDS/REFERENCES type article... Erik On Thu, 5 May 1994, DIRK BROER wrote: > Before we decide on what computer to use etc shouldn't we decide what the > operating enviroment or rather the requirements are? > > Ouput would be a PWM signal to the injectors. You could vary the start > time and the end time of each injector to get sequential port injection. > > For input I suspect we'd need: > O2 sensor - what better way to set the car for part throttle cruise. > Throttle Position sensor > temperature sensor > RPM sensor - maybe an engine position sensor - so you know exactly which > cylinder needs fuel / spark next (distributer mounted of course). > and then either a MAP or MAF sensor. > maybe Humidity sensor? - or altimeter? > > Is that all? > > If that is all perhaps we could also get an idea on what kinda of data > rates are needed. > > 02 sensors react relatively slow - maybe 10 readings a sec? > TPS - sensors - at least 10 readings a second if not more > Temp sensors - 1 reading a second > RPM sensor - at 10,000rpm (why not?) - that 600,000 degrees per second. 4 > bumps on the crank shaft (ie - crank triggered ignition) would mean less > than 1000 per second... > MAP or MAF sensor - 1 per second - maybe more... 10? > > The system would have to work at: > Startup > Idle > part throotle cruise > WOT > anything else? > > > Next post what would the algorithm be like? > > Dirk > > > From Diy_Efi-Owner Fri May 6 02:47:17 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA08969; Fri, 6 May 94 02:47:17 GMT Received: from knuth.mtsu.edu by coulomb.eng.ohio-state.edu via SMTP (920330.SGI/920502.SGI) for /usr/local/mail/majordomo/wrapper resend -p bulk -M 10000 -l Diy_Efi -f Diy_Efi-Owner -h coulomb.eng.ohio-state.edu -s -r DIY_EFI@coulomb.eng.ohio-state.edu diy_efi-outgoing id AA08963; Thu, 5 May 94 22:47:14 -0400 Received: by knuth.mtsu.edu (Smail3.1.28.1 #17) id m0pzFx4-000AVPC; Thu, 5 May 94 21:47 CDT Message-Id: From: lusky@knuth.mtsu.edu (Jonathan R. Lusky) Subject: Re: your mail To: DIY_EFI Date: Thu, 5 May 1994 21:47:46 -0500 (CDT) In-Reply-To: <9405060145.AA08135@coulomb.eng.ohio-state.edu> from "John S Gwynne" at May 5, 94 09:45:14 pm X-Mailer: ELM [version 2.4 PL23] Content-Type: text Content-Length: 2537 Sender: Diy_Efi-Owner Precedence: bulk Reply-To: DIY_EFI@coulomb.eng.ohio-state.edu > | Is it 8048, 8051, 8086, 80186, 6800, 6500, 68000, or what? > | > > Lets keep all the discussions going. I am personally more interested in > the control algorithms than the hardware itself, but the hardware issues > need to be resolved also. We have two basic choices: > microcontroller (8052, 6811, etc). and CPU (80x86, 680x0). I would say > that in the interests of cheapness and simplicity the microcontroller > provides the best solution, but that is IMO. Maybe we should bat ideas > around for a week or so, then have a vote. we are probably still picking > up new people who have valuable opinions, so no need to rush things. I'm > enjoying just reading what has been posted so far. I'm partial to the 6811 just for two reasons, simplicity and popularity. Maybe this isn't true in other circles, but it seems that everyone uses the 68HC11 for small custom microcontrollers nowadays, and I believe it will have more support software available (cross compilers, etc) than just about anything else for this type of application. Of course, with an 80x86 crosscompilers wouldn't really be necessary, but I think simpler hardware required to use the 68HC11 is more significant. This is my laymans view (I'm not a EE type, I just had a good experience with a 68HC11 based telemetry system that someone built for me). > also, if anyone has access to things we are likely to need like pcb routing > and etching, compilers for whatever processor we decide on, etc., they > should speak up. Hardly anyone will have all the > resources to do all this, but between us we should be able to put all the > pieces together. Absolutely... look at some of the great free unix software out there for inspiration as to what a group of people can do when they put their heads together. The thing that excites me the most about a good DIY FI system is the potential for customization and expansion, something totally lacking in the current aftermarket FI systems. For CNG systems for example, it'd be really nice to have fuel temperature and rail pressure as inputs to the ECM. Nitrous, PWM EGR, boost control, adaptability to a wide range of OEM sensors, torque convertor lockup, UEGO support, etc. Lotsa things that the average person may not need, but being able to write a module and add it to the code to do some of these thing would be really nice. -- Jonathan R. Lusky -- lusky@knuth.mtsu.edu "Turbos are nice but I'd rather be blown!" 89 Jeep Wrangler - 258 / pile of junk! 80 Toyota Celica - 20R / 5spd From Diy_Efi-Owner Fri May 6 02:57:28 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA09029; Fri, 6 May 94 02:57:28 GMT Received: from localhost.eng.ohio-state.edu by coulomb.eng.ohio-state.edu via SMTP (920330.SGI/920502.SGI) for /usr/local/mail/majordomo/wrapper resend -p bulk -M 10000 -l Diy_Efi -f Diy_Efi-Owner -h coulomb.eng.ohio-state.edu -s -r DIY_EFI@coulomb.eng.ohio-state.edu diy_efi-outgoing id AA09023; Thu, 5 May 94 22:57:26 -0400 Message-Id: <9405060257.AA09023@coulomb.eng.ohio-state.edu> To: DIY_EFI In-Reply-To: Your message of "Thu, 05 May 94 21:44:17 EDT." <9405060144.AA08036@coulomb.eng.ohio-state.edu> Date: Thu, 05 May 94 22:57:26 -0400 From: John S Gwynne Sender: Diy_Efi-Owner Precedence: bulk Reply-To: DIY_EFI@coulomb.eng.ohio-state.edu In message <9405060144.AA08036@coulomb.eng.ohio-state.edu> , you write: | What voltage does an injector need to open? If it is an electro-magnetic | device like a solenoid then voltage isn't really important, as long as | there is plenty of current. If the voltage level is important, then it | would be simpler to use a regulator to keep the voltage constant at, say, | 10 volts. If battery voltage drops below that, the car isn't going to run | well anyway, regardless of what the injectors are doing. Question: how good is the fuel pump regulation as the supply voltage varies? John S Gwynne Gwynne.1@osu.edu _______________________________________________________________________________ T h e O h i o - S t a t e U n i v e r s i t y ElectroScience Laboratory, 1320 Kinnear Road, Columbus, Ohio 43212, USA Telephone: (614) 292-7981 * Fax: (614) 292-7292 ------------------------------------------------------------------------------- From Diy_Efi-Owner Fri May 6 03:00:58 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA09084; Fri, 6 May 94 03:00:58 GMT Received: from dopey.cc.utexas.edu by coulomb.eng.ohio-state.edu via SMTP (920330.SGI/920502.SGI) for /usr/local/mail/majordomo/wrapper resend -p bulk -M 10000 -l Diy_Efi -f Diy_Efi-Owner -h coulomb.eng.ohio-state.edu -s -r DIY_EFI@coulomb.eng.ohio-state.edu diy_efi-outgoing id AA09078; Thu, 5 May 94 23:00:56 -0400 Received: (from efrank@localhost) by dopey.cc.utexas.edu (8.6.8.1/8.6.6/cc-wf-sunos.mc-1.1) id WAA22008; Thu, 5 May 1994 22:00:53 -0500 Date: Thu, 5 May 1994 22:00:52 -0500 (CDT) From: The_Mechanic Subject: Re: your mail To: DIY_EFI In-Reply-To: <9405060145.AA08135@coulomb.eng.ohio-state.edu> Message-Id: Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: Diy_Efi-Owner Precedence: bulk Reply-To: DIY_EFI@coulomb.eng.ohio-state.edu On Thu, 5 May 1994, John S Gwynne wrote: > Lets keep all the discussions going. I am personally more interested in > the control algorithms than the hardware itself, but the hardware issues > need to be resolved also. We have two basic choices: > microcontroller (8052, 6811, etc). and CPU (80x86, 680x0). I would say > that in the interests of cheapness and simplicity the microcontroller > provides the best solution, but that is IMO. Maybe we should bat ideas > around for a week or so, then have a vote. we are probably still picking > up new people who have valuable opinions, so no need to rush things. I'm > enjoying just reading what has been posted so far. > > also, if anyone has access to things we are likely to need like pcb routing > and etching, compilers for whatever processor we decide on, etc., they > should speak up. Hardly anyone will have all the > resources to do all this, but between us we should be able to put all the > pieces together. > > --steve > > > My vote is for an 80xx CPU. Seems far more flexible than the microcontrollers... Erik From Diy_Efi-Owner Fri May 6 03:09:44 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA09128; Fri, 6 May 94 03:09:44 GMT Received: from knuth.mtsu.edu by coulomb.eng.ohio-state.edu via SMTP (920330.SGI/920502.SGI) for /usr/local/mail/majordomo/wrapper resend -p bulk -M 10000 -l Diy_Efi -f Diy_Efi-Owner -h coulomb.eng.ohio-state.edu -s -r DIY_EFI@coulomb.eng.ohio-state.edu diy_efi-outgoing id AA09122; Thu, 5 May 94 23:08:43 -0400 Received: by knuth.mtsu.edu (Smail3.1.28.1 #17) id m0pzGHf-000AVRC; Thu, 5 May 94 22:09 CDT Message-Id: From: lusky@knuth.mtsu.edu (Jonathan R. Lusky) Subject: Re: your mail To: DIY_EFI Date: Thu, 5 May 1994 22:09:03 -0500 (CDT) In-Reply-To: <9405060144.AA08036@coulomb.eng.ohio-state.edu> from "John S Gwynne" at May 5, 94 09:44:17 pm X-Mailer: ELM [version 2.4 PL23] Content-Type: text Content-Length: 1814 Sender: Diy_Efi-Owner Precedence: bulk Reply-To: DIY_EFI@coulomb.eng.ohio-state.edu > What voltage does an injector need to open? If it is an electro-magnetic > device like a solenoid then voltage isn't really important, as long as > there is plenty of current. If the voltage level is important, then it > would be simpler to use a regulator to keep the voltage constant at, say, > 10 volts. If battery voltage drops below that, the car isn't going to run > well anyway, regardless of what the injectors are doing. The way "standard" peak and hold injectors are designed to be driven is with an initial pulse of 4 amps to pop open the injector and a continuous 1 amp to keep the injector open. Since the injector resistance is fairly constant (don't know what is off the top of my head), you can calculate what voltage is required. I'm not that familiar with standard 4/1 peak & hold drivers, but I believe they will cover the regulation for input voltages higher than required voltage to the injector. The voltage correction table is necessary for voltages lower than that voltage. Regulating at 10 volts is probably 1) too low to get 4 amps to the injectors to open, and 2) higher than the voltage some vehicles may see during cranking. Heres the voltage correction table that came in our EFI Technologies ECU: V microseconds to add to on time > 15.75 400 14.63 432 13.5 480 12.38 608 11.25 784 10.13 992 9.00 1248 7.88 1568 6.75 2000 5.63 2576 < 4.50 3296 I'm not sure why they began the table with 400 microseconds, that may have been the estimated opening time for our injectors (GM Multec). Also note that the EFI Technologies box doesn't just look up the values, it also does interpolation. -- Jonathan R. Lusky -- lusky@knuth.mtsu.edu "Turbos are nice but I'd rather be blown!" 89 Jeep Wrangler - 258 / pile of junk! 80 Toyota Celica - 20R / 5spd From Diy_Efi-Owner Fri May 6 03:31:50 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA09162; Fri, 6 May 94 03:31:50 GMT Received: from knuth.mtsu.edu by coulomb.eng.ohio-state.edu via SMTP (920330.SGI/920502.SGI) for /usr/local/mail/majordomo/wrapper resend -p bulk -M 10000 -l Diy_Efi -f Diy_Efi-Owner -h coulomb.eng.ohio-state.edu -s -r DIY_EFI@coulomb.eng.ohio-state.edu diy_efi-outgoing id AA09156; Thu, 5 May 94 23:31:46 -0400 Received: by knuth.mtsu.edu (Smail3.1.28.1 #17) id m0pzGe5-000AVPC; Thu, 5 May 94 22:32 CDT Message-Id: From: lusky@knuth.mtsu.edu (Jonathan R. Lusky) Subject: Re: Some thoughts and questions on EFI To: DIY_EFI Date: Thu, 5 May 1994 22:32:13 -0500 (CDT) In-Reply-To: from "The_Mechanic" at May 5, 94 09:43:37 pm X-Mailer: ELM [version 2.4 PL23] Content-Type: text Content-Length: 2651 Sender: Diy_Efi-Owner Precedence: bulk Reply-To: DIY_EFI@coulomb.eng.ohio-state.edu The_Mechanic writes: > A couple of quick questions (from an electronics-ignorant ME type guy): > > - the 68HC11 microcontroller chip is an 8 bit unit, right? Is there a > similiar chip available in a 16 bit architecture? Would it even be > nescessary? Yep, its 8bit. I'm not sure whats available in 16bit. I believe the new GM stuff is ?68333? based. My EFI Technologies ECU was 16bit, 12mhz but I don't know what chip. > - it would be great to develop a system with some accompanying software > so that a laptop PC could interface "Real time" with the engine computer. > Adjustments could be made "on the fly" with the engine running. This > would be wonderful on the dyno. Also, an interface that would port > information over to the Superflow SF-901 software would also be real > cool. Are these out of reach? Being able to talk to the ECM with the engine running is a must. One nice thing I liked about the Stewart/Stevenson GFI system was its self-calibration software. You put the car on the chassis dyno and run the calibration software, and it graphically displays and array of boxes representing RPM vs MAP locations. When the engine is operating at the MAP,RPM for a box on the screen, that box flashes. If you mantain that MAP,RPM, the ECM adjusts the mixture and watches the O2 sensor. Once it has spent enough time on that box to get a valid data point, the box on the screen changes color, and the driver fumbles around with the throttle and load until he gets to another box, and repeats for all the boxes that he can get to. I believe we went thru this 3 times without EGR & PCV and twice with them. In one afternoon it was possible to have a perfect steady state map, with transient response calibration set to an initial guess and fine tuned on the road. Of course, with CNG you can get away with running stoich at high load, so this approach wouldn't apply to high load with gasoline. On the other hand, high load could be done this way I imagine with EGT for feedback instead of O2. Something else I've seen that I liked was something the EFI-Tech system had. There was a interface box that went between the ECU and the laptop. ZThe interface box had BIG knobs to adjust fuel (+/- 30%) and spark (+/- 15 deg) on the fly. The knobs also functioned without the laptop connected, although you couldn't tell exactly how much you were changing things with the laptop and monitor software. Anyway, this is just food for thought. -- Jonathan R. Lusky -- lusky@knuth.mtsu.edu "Turbos are nice but I'd rather be blown!" 89 Jeep Wrangler - 258 / pile of junk! 80 Toyota Celica - 20R / 5spd From Diy_Efi-Owner Fri May 6 03:34:21 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA09178; Fri, 6 May 94 03:34:21 GMT Received: from knuth.mtsu.edu by coulomb.eng.ohio-state.edu via SMTP (920330.SGI/920502.SGI) for /usr/local/mail/majordomo/wrapper resend -p bulk -M 10000 -l Diy_Efi -f Diy_Efi-Owner -h coulomb.eng.ohio-state.edu -s -r DIY_EFI@coulomb.eng.ohio-state.edu diy_efi-outgoing id AA09172; Thu, 5 May 94 23:34:18 -0400 Received: by knuth.mtsu.edu (Smail3.1.28.1 #17) id m0pzGgZ-000AVPC; Thu, 5 May 94 22:34 CDT Message-Id: From: lusky@knuth.mtsu.edu (Jonathan R. Lusky) Subject: archiving this list To: DIY_EFI Date: Thu, 5 May 1994 22:34:47 -0500 (CDT) X-Mailer: ELM [version 2.4 PL23] Content-Type: text Content-Length: 210 Sender: Diy_Efi-Owner Precedence: bulk Reply-To: DIY_EFI@coulomb.eng.ohio-state.edu Is this list being archived anywhere? -- Jonathan R. Lusky -- lusky@knuth.mtsu.edu "Turbos are nice but I'd rather be blown!" 89 Jeep Wrangler - 258 / pile of junk! 80 Toyota Celica - 20R / 5spd From Diy_Efi-Owner Fri May 6 03:49:51 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA09221; Fri, 6 May 94 03:49:51 GMT Received: from knuth.mtsu.edu by coulomb.eng.ohio-state.edu via SMTP (920330.SGI/920502.SGI) for /usr/local/mail/majordomo/wrapper resend -p bulk -M 10000 -l Diy_Efi -f Diy_Efi-Owner -h coulomb.eng.ohio-state.edu -s -r DIY_EFI@coulomb.eng.ohio-state.edu diy_efi-outgoing id AA09215; Thu, 5 May 94 23:49:38 -0400 Received: by knuth.mtsu.edu (Smail3.1.28.1 #17) id m0pzGvQ-000AVRC; Thu, 5 May 94 22:50 CDT Message-Id: From: lusky@knuth.mtsu.edu (Jonathan R. Lusky) Subject: reply address To: DIY_EFI Date: Thu, 5 May 1994 22:50:08 -0500 (CDT) X-Mailer: ELM [version 2.4 PL23] Content-Type: text Content-Length: 406 Sender: Diy_Efi-Owner Precedence: bulk Reply-To: DIY_EFI@coulomb.eng.ohio-state.edu The Reply-To: line on messages from the list seems to be messed up... I just noticed I had sent several replies to DIY_EFI@coulomb.eng.ohio-state.edu@coulomb.eng.ohio-state.edu If those messages hit the bit bucket, I'll resend them. -- Jonathan R. Lusky -- lusky@knuth.mtsu.edu "Turbos are nice but I'd rather be blown!" 89 Jeep Wrangler - 258 / pile of junk! 80 Toyota Celica - 20R / 5spd From Diy_Efi-Owner Fri May 6 07:49:49 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA09477; Fri, 6 May 94 07:49:49 GMT Received: from [202.14.102.1] by coulomb.eng.ohio-state.edu via SMTP (920330.SGI/920502.SGI) for /usr/local/mail/majordomo/wrapper resend -p bulk -M 10000 -l Diy_Efi -f Diy_Efi-Owner -h coulomb.eng.ohio-state.edu -s -r DIY_EFI@coulomb.eng.ohio-state.edu diy_efi-outgoing id AA09471; Fri, 6 May 94 03:49:37 -0400 Received: from localhost (steveb@localhost) by kcbbs.gen.nz (8.5/8.5) id TAA28966; Fri, 6 May 1994 19:44:20 +1200 From: Steve Baldwin Message-Id: <199405060744.TAA28966@kcbbs.gen.nz> Subject: Intro / CPU types To: DIY_EFI Date: Fri, 6 May 1994 19:44:19 +1200 (NZST) X-Mailer: ELM [version 2.4 PL21] Content-Type: text Content-Length: 1969 Sender: Diy_Efi-Owner Precedence: bulk Reply-To: DIY_EFI@coulomb.eng.ohio-state.edu Hi, I am an EE in New Zealand (go down to Australia and turn left). I guess I am specialised in embedded control and microcontrollers. I was an Application Engineer for Philips for a few years mostly developing development tools for 8051's et al. I'm now back in the real world designing industrial controllers. My project engine is a little different. A blown Flathead V8. The main intention is to piss off traditionalist rodders and have some fun learning about the physics of combustion. I've used quite a variety of microcontrollers and before we dive in and declare that XYZ is the only true way, it would make some sense to determine what capabilities the system requires. For example, take a hypothetical, worst case engine and take some punts as to what resources it will require. Say a V8 running up to 8000rpm. How many analogue inputs do we need ? What resolution is realistic ? (Note the word 'realistic'. 34 14 bit A/D channels is a bit over the top) IMHO, the more you can stuff in a microcontroller, the better. There are several uC's around that are intended for ECU use. I'm building a completely automated astronomical obsrvatory at the moment using a Philips 80C552. This would be an ideal candidate. 8051 core, 8 channel 10 bit A/D, 2 PWM, 3 timers (one with 4 capture/compare registers), I2C (for EEPROM, RTC, etc), ports, blah, blah, blah. Disadvantage - Only assemblers available for free (at the moment). I have access to PCB layout CAD and can get good pricing on PCB's. I also have a good relationship with the local component suppliers (advantage of working for one the largest electronics manufacturers in the country). As for EPROMs etc. Flash is the way to go. Intel have boot block parts and some others have sector erasable parts. This means that you can be running from one section while programming another. Oops ! Gone into waffle mode. Sorry ! Anyway.....decide what it has to do and _then_ decide what can do it. Steve.