28 pin chips in 24 pin dme?
11-14-2001, 11:28 PM
#1
Three Wheelin'
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28 pin chips in 24 pin dme?
Anyone out there tried to put 28 pin chips into a 24 pin dme? I've always read that the last four pins of the 28 pin chips are unused and the dme's are otherwise the same.
http://www.tech-session.com/Paragon/...e_chip_007.jpg
From this picture, it appears that the chips would probably hit the red capacitor(?) to the right of it, but it may just fit. I am not averse to bending or even cutting the the extra pins on the chips.
I am planning on putting a K26/8 on my '86 and would like to use aftermarket chips designed for this turbo.
Thanks,
Steve Lavigne
'86 951
http://www.tech-session.com/Paragon/...e_chip_007.jpg
From this picture, it appears that the chips would probably hit the red capacitor(?) to the right of it, but it may just fit. I am not averse to bending or even cutting the the extra pins on the chips.
I am planning on putting a K26/8 on my '86 and would like to use aftermarket chips designed for this turbo.
Thanks,
Steve Lavigne
'86 951
11-15-2001, 02:00 PM
#2
Racer
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No, pin 28 is power for the EPROM and wouldn't be connected in a 24-pin socket. The four additional pins are Vpp, A12, Vcc, and _PGM.
You could stick a 24 pin EPROM in a 28 pin
socket as long as pin 26 (a NC for the 28 pin chip) had power. In this case the EPROM would be mapped to two different memory locations.
The deal with 24/28 pin Motronics is that they all contain 8k of ROM of some type. For the 24 pin configurations, 4K is embedded in microcontroller and 4K is in the external EPROM. For the 28-pin, the microcontroller has no ROM and all 8K is contained in the external EPROM. So even if you could stick a
28-pin chip in a 24-pin socket the memory addressing would be messed up when using standard aftermarket or stock chips.
What you want to do is transfer the timing and fuel maps from the other chip to your 24-pin chip. These are contained in the last 4K of the 28-pin chips.
You could stick a 24 pin EPROM in a 28 pin
socket as long as pin 26 (a NC for the 28 pin chip) had power. In this case the EPROM would be mapped to two different memory locations.
The deal with 24/28 pin Motronics is that they all contain 8k of ROM of some type. For the 24 pin configurations, 4K is embedded in microcontroller and 4K is in the external EPROM. For the 28-pin, the microcontroller has no ROM and all 8K is contained in the external EPROM. So even if you could stick a
28-pin chip in a 24-pin socket the memory addressing would be messed up when using standard aftermarket or stock chips.
What you want to do is transfer the timing and fuel maps from the other chip to your 24-pin chip. These are contained in the last 4K of the 28-pin chips.
11-15-2001, 02:46 PM
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Three Wheelin'
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Hmm... I've been thinking about getting an eprom programmer and trying to learn how to work with the stock computer.
It sounds like you have some experience burning chips. Can you direct me to some information on programming them. I've found some motronic information off some Swedish website with fuel and ignition maps for a volvo. Does Bonneville Motor Works offer software to program with our DME's? Alternatively, just location and value conversion information would be sufficient for programming. I'd really like to get some information on the KLR, so it could be used as a boost controller instead of having to use some **** or aftermarket box.
Thanks,
-Steve
It sounds like you have some experience burning chips. Can you direct me to some information on programming them. I've found some motronic information off some Swedish website with fuel and ignition maps for a volvo. Does Bonneville Motor Works offer software to program with our DME's? Alternatively, just location and value conversion information would be sufficient for programming. I'd really like to get some information on the KLR, so it could be used as a boost controller instead of having to use some **** or aftermarket box.
Thanks,
-Steve
