1995 OBD1 Diag tool
#92
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Aren't there any existing cables that would work right out of the box ?
I don't know much in electronics. But I've seen that the Honda guys use a Nokia cell phone cable as a USB <->TTL cable to access their ECU. That would be great if we could do the same thing.
With USB we could start thinking about a MacOS version of the code for us that have not seen a serial port for years :-)
Otherwise I'm interested in a PCB, if one is getting built.
-Guillaume
I don't know much in electronics. But I've seen that the Honda guys use a Nokia cell phone cable as a USB <->TTL cable to access their ECU. That would be great if we could do the same thing.
With USB we could start thinking about a MacOS version of the code for us that have not seen a serial port for years :-)
Otherwise I'm interested in a PCB, if one is getting built.
-Guillaume
#94
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Guillaume,
I'm not sure I understand your question.
You may be able to use the USB port of a Windows PC, seems that would include new MACs running Windows OS.
Here is part of a 964 thread, you can search there for more info.
"- USB-serial converter issues: I've found a USB converter that works with the ECU's funky baud rate. It's made by SIIG and uses the FT8U232AM chip. I had to install the latest drivers from here to get it to work properly as the drivers included were outdated. I expect any usb converter that uses the ftdi chip will work."
Ray
I'm not sure I understand your question.
You may be able to use the USB port of a Windows PC, seems that would include new MACs running Windows OS.
Here is part of a 964 thread, you can search there for more info.
"- USB-serial converter issues: I've found a USB converter that works with the ECU's funky baud rate. It's made by SIIG and uses the FT8U232AM chip. I had to install the latest drivers from here to get it to work properly as the drivers included were outdated. I expect any usb converter that uses the ftdi chip will work."
Ray
#95
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cowtown,
I agree with Lorens crank about the capacitor. Interface could use some bulk capacitance.
A ceramic cap 0.1uF 25 Volt could replace the .22uF
Vishay has at least 2 choices, the mono-kap is cheaper.
A104K15X7RF5TAA a ceramic axial, .0uF 50V X7R length 0.150"
K104Z15Y5VE5TL2 mono-kap 0.1uF 25V Y5V lead spacing 2.54mm
The second cap will be an aluminum electrolytic. Needs a + sign as it is polarized.
I used 100uF 25WV Radial @ 0.25" diameter.
Vishay 515D107M025AA6A
No magic in the capacitance values I picked. But ceramic for high frequency noise and bulk for low.
The + Volts input can be 14Volts so a 16WV cap would not be a good idea.
The resistors can be 1/4W 10%.
I'm done.
Ray
I agree with Lorens crank about the capacitor. Interface could use some bulk capacitance.
A ceramic cap 0.1uF 25 Volt could replace the .22uF
Vishay has at least 2 choices, the mono-kap is cheaper.
A104K15X7RF5TAA a ceramic axial, .0uF 50V X7R length 0.150"
K104Z15Y5VE5TL2 mono-kap 0.1uF 25V Y5V lead spacing 2.54mm
The second cap will be an aluminum electrolytic. Needs a + sign as it is polarized.
I used 100uF 25WV Radial @ 0.25" diameter.
Vishay 515D107M025AA6A
No magic in the capacitance values I picked. But ceramic for high frequency noise and bulk for low.
The + Volts input can be 14Volts so a 16WV cap would not be a good idea.
The resistors can be 1/4W 10%.
I'm done.
Ray
#96
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If anyone has suggestions/corrections, I'm all ears!
I think the PCB is almost there. The components may be a bit close but I think soldering is do-able. Each white dot in the grid is 1/10" from the adjacent white dot. Traces are 0.025" and board size is 2.5x3.8". EDIT - I'll put in a couple holes for extra cap filters on the supply and leave it up to the builders what to put in there.
If others want to try this board, you're going to need to find an enclosure. I checked out an electronics surplus store (HSC) and found a 3x5" project box that will work with a little creativity. I placed four mounting holes on the PCB but they are not meant to conform to a standard enclosure (if there is such a thing).
My plan is get feedback here, do a final check, then order a 3-board package for $60 and try it out. So two risk-takers could join me on the first run, or you can wait and see if they work and then do another run. Ray, if you want one of the first-run boards I'd be glad to send it to you no charge. And thanks again for your work!
EDIT - this layout is obsolete, so I'm removing it. See below for newest --Colin
I think the PCB is almost there. The components may be a bit close but I think soldering is do-able. Each white dot in the grid is 1/10" from the adjacent white dot. Traces are 0.025" and board size is 2.5x3.8". EDIT - I'll put in a couple holes for extra cap filters on the supply and leave it up to the builders what to put in there.
If others want to try this board, you're going to need to find an enclosure. I checked out an electronics surplus store (HSC) and found a 3x5" project box that will work with a little creativity. I placed four mounting holes on the PCB but they are not meant to conform to a standard enclosure (if there is such a thing).
My plan is get feedback here, do a final check, then order a 3-board package for $60 and try it out. So two risk-takers could join me on the first run, or you can wait and see if they work and then do another run. Ray, if you want one of the first-run boards I'd be glad to send it to you no charge. And thanks again for your work!
EDIT - this layout is obsolete, so I'm removing it. See below for newest --Colin
Last edited by cowtown; 08-11-2006 at 02:56 PM.
#97
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Raycm,
Yes I understand your solution works with a USB-> serial converter. I already have a USB-RS232 converter, and that's why I'm interested in getting one of those PCBs if possible.
My question was : aren't there already some other solutions
(like the USB Nokia cellphone cable ?), that achieve the same goal as your custom-made circuit ?
It would be nice if we could buy a nice, fully integrated cable and just remove the nokia plug at the end, instead of soldering components and build our own circuit. That would make things easier for most other RLers.
The USB subject is just that if it was native USB instead of going through a USB-serial converter, it would be even better, as serial ports are phasing out. One single cable and that would be it.
Some pointers :
The Nokia-cable thing that the Honda guys use :
http://www.pgmfi.org/twiki/bin/view/Library/DataLogging
http://www.pgmfi.org/twiki/bin/view/...bleDatalogging
http://www.futurlec.com/USB.shtml : Some people used the USBMOD3 to have the Valentine V1 talk to their PC-in-the-car...
It's also serial-TTL stuff so to me it looks close enough![Big Grin](https://rennlist.com/forums/images/smilies/biggrin.gif)
As you've already realized, I don't know anything about electronics. It's just that I have a hard time thinking that no other domain uses the same kind of communication as our OBD, and that such a cable does not exist already. But I'm probably wrong...
-Guillaume
Yes I understand your solution works with a USB-> serial converter. I already have a USB-RS232 converter, and that's why I'm interested in getting one of those PCBs if possible.
My question was : aren't there already some other solutions
(like the USB Nokia cellphone cable ?), that achieve the same goal as your custom-made circuit ?
It would be nice if we could buy a nice, fully integrated cable and just remove the nokia plug at the end, instead of soldering components and build our own circuit. That would make things easier for most other RLers.
The USB subject is just that if it was native USB instead of going through a USB-serial converter, it would be even better, as serial ports are phasing out. One single cable and that would be it.
Some pointers :
The Nokia-cable thing that the Honda guys use :
http://www.pgmfi.org/twiki/bin/view/Library/DataLogging
http://www.pgmfi.org/twiki/bin/view/...bleDatalogging
http://www.futurlec.com/USB.shtml : Some people used the USBMOD3 to have the Valentine V1 talk to their PC-in-the-car...
It's also serial-TTL stuff so to me it looks close enough
![Big Grin](https://rennlist.com/forums/images/smilies/biggrin.gif)
As you've already realized, I don't know anything about electronics. It's just that I have a hard time thinking that no other domain uses the same kind of communication as our OBD, and that such a cable does not exist already. But I'm probably wrong...
-Guillaume
Originally Posted by raycm
Guillaume,
I'm not sure I understand your question.
You may be able to use the USB port of a Windows PC, seems that would include new MACs running Windows OS.
Here is part of a 964 thread, you can search there for more info.
"- USB-serial converter issues: I've found a USB converter that works with the ECU's funky baud rate. It's made by SIIG and uses the FT8U232AM chip. I had to install the latest drivers from here to get it to work properly as the drivers included were outdated. I expect any usb converter that uses the ftdi chip will work."
Ray
I'm not sure I understand your question.
You may be able to use the USB port of a Windows PC, seems that would include new MACs running Windows OS.
Here is part of a 964 thread, you can search there for more info.
"- USB-serial converter issues: I've found a USB converter that works with the ECU's funky baud rate. It's made by SIIG and uses the FT8U232AM chip. I had to install the latest drivers from here to get it to work properly as the drivers included were outdated. I expect any usb converter that uses the ftdi chip will work."
Ray
#98
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Okay, I tweaked the traces a little more and put in an order for 3 PCBs. I'll get them Thursday of next week and report back when I've got one built. You just can't buy entertainment like this at the movies. ![Big Grin](https://rennlist.com/forums/images/smilies/biggrin.gif)
Ray, if you want one of the PCBs, shoot me a mailing address in a private message.
Colin
![Big Grin](https://rennlist.com/forums/images/smilies/biggrin.gif)
Ray, if you want one of the PCBs, shoot me a mailing address in a private message.
Colin
#99
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Guillaume,
I'll need to spend a little time looking at your post before I can answer.
There is one problem, the 1995 993 has a different OBD interface including operation from the 964 and the 1996 and later OBDII autos. OBDII has a standard pinout and operation for the DME. Manufacturers then add their own enhancements. A OBDII interface/application will work on 1996 and later vehicles for the government required functions.
Ray
I'll need to spend a little time looking at your post before I can answer.
There is one problem, the 1995 993 has a different OBD interface including operation from the 964 and the 1996 and later OBDII autos. OBDII has a standard pinout and operation for the DME. Manufacturers then add their own enhancements. A OBDII interface/application will work on 1996 and later vehicles for the government required functions.
Ray
#100
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Originally Posted by cowtown
Okay, I tweaked the traces a little more and put in an order for 3 PCBs. I'll get them Thursday of next week and report back when I've got one built. You just can't buy entertainment like this at the movies. ![Big Grin](https://rennlist.com/forums/images/smilies/biggrin.gif)
Ray, if you want one of the PCBs, shoot me a mailing address in a private message.
Colin
![Big Grin](https://rennlist.com/forums/images/smilies/biggrin.gif)
Ray, if you want one of the PCBs, shoot me a mailing address in a private message.
Colin
Done.
Ray
#101
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Here's the original 964 interface posted 2 years ago on Rennlist
which provides true +/-12 RS232 translation and requires no
switches because of the simplicity of the 964 OBDI:
which provides true +/-12 RS232 translation and requires no
switches because of the simplicity of the 964 OBDI:
#102
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Note: For those that dislike cabling, a DB9 RS232 to Bluetooth
and Bluetooth to DB9 RS232 can be used to replace the cable.
Check here for more info: ( www.aircable.net )
And for those that have a Bluetooth enabled PC, a single
Bluetooth to RS232 DB9 connected to the interface board
replaces the cable, e.g. PC (laptop/desktop) now on a
bench/table, and provides PC isolation.
Or for those not wishing to build electronics, here's another
solution which requires just software mods, but it can be either
RS232 or USB:
www.bb-elec.com/product_family.asp?FamilyId=222
and Bluetooth to DB9 RS232 can be used to replace the cable.
Check here for more info: ( www.aircable.net )
And for those that have a Bluetooth enabled PC, a single
Bluetooth to RS232 DB9 connected to the interface board
replaces the cable, e.g. PC (laptop/desktop) now on a
bench/table, and provides PC isolation.
Or for those not wishing to build electronics, here's another
solution which requires just software mods, but it can be either
RS232 or USB:
www.bb-elec.com/product_family.asp?FamilyId=222
Last edited by Lorenfb; 08-05-2006 at 05:04 AM.
#103
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Loren,
I worked with this type of "cables", but you have to pre-choose the baudrate. You can't change the baudrate via user application. Some aircables are equipped with dip switches to select the output/pinput baudrate and others can be setup by a special command mode. So if you are using this with scantool on different ecus and with different baudrates you must a setup. I think this is more complicate as using a real cable...
PDriver
I worked with this type of "cables", but you have to pre-choose the baudrate. You can't change the baudrate via user application. Some aircables are equipped with dip switches to select the output/pinput baudrate and others can be setup by a special command mode. So if you are using this with scantool on different ecus and with different baudrates you must a setup. I think this is more complicate as using a real cable...
PDriver
#104
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"Some aircables are equipped with dip switches to select the output/pinput baudrate and others can be setup by a special command mode."
The baud rate of the software app is not continuously variable and thus the
Bluetooth device baud rate can be set to what the OBD & software requires.
So, once the devices are properly setup/programmed, not a real issue.
The baud rate of the software app is not continuously variable and thus the
Bluetooth device baud rate can be set to what the OBD & software requires.
So, once the devices are properly setup/programmed, not a real issue.
#105
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Loren, that's right.
But some ecus uses different baudrates, e.g. if I switch from 993's motronic (9600bps) to the climate control(4800bps). This will be a problem when we use Dough's scantool software. For other OBD-software, which use a intelligent interface like ELM, there is only a one setup needed and a cable replacement via bluetooth is a great feature.
Can we use ELM in conjunction with 964/993? Any experiences with this?
PDriver
But some ecus uses different baudrates, e.g. if I switch from 993's motronic (9600bps) to the climate control(4800bps). This will be a problem when we use Dough's scantool software. For other OBD-software, which use a intelligent interface like ELM, there is only a one setup needed and a cable replacement via bluetooth is a great feature.
Can we use ELM in conjunction with 964/993? Any experiences with this?
PDriver