265 Hemi to efi

Converting To Delco ECU From Carby Or Other Injection Systems
User avatar
Posts: 6364
Joined: Mon Oct 08, 2012 6:41 pm
Location: Kyneton, Vic

Re: 265 Hemi to efi

Postby vlad01 » Sat Aug 17, 2019 9:53 pm

8 bits in a byte. Chips (hardware) are always denoted in bits while files (software) are generally always in bytes. 512Kb (little b is bits) is equal to 64KB (big B is bytes)

12P is 32KB non stacked.
11P is 64KB non stacked.

If you are using 12P you either stack it twice to make 32KB+32KB making it fit 512Kb prom perfect or you run an offset of 8000 on the burner, that puts the 32Kb file at the bottom of the memory array.

The reason it needs to be at the bottom is becasue the ECU starting reading the data from bottom up, the start of the file is the essentially at the end of the proms address range. ie. FFFF

That is why we need to do this to make it work.
I'm the director of VSH (Vlad's Spec Holden), because HSV were doing it ass about.

Posts: 365
Joined: Sun Jul 04, 2010 3:15 pm
Location: NZ

Re: 265 Hemi to efi

Postby VK_3800 » Sun Aug 18, 2019 8:35 am

heff0018 wrote:Thanks for the reply I only entered the file offset this time. Strange I still get an error but now the address is 0x008001.

Just to add my two cents on software I'm not familiar with, but wouldn't the file offset be 0 and you'd use the device offset? You want the entire file from the beginning, but program it into the last part of the prom.

Posts: 727
Joined: Tue Apr 21, 2015 1:42 pm

Re: 265 Hemi to efi

Postby heff0018 » Sun Aug 18, 2019 12:25 pm

vlad01 wrote:8 bits in a byte. Chips (hardware) are always denoted in bits while files (software) are generally always in bytes. 512Kb (little b is bits) is equal to 64KB (big B is bytes)

12P is 32KB non stacked.
11P is 64KB non stacked.

If you are using 12P you either stack it twice to make 32KB+32KB making it fit 512Kb prom perfect or you run an offset of 8000 on the burner, that puts the 32Kb file at the bottom of the memory array.

The reason it needs to be at the bottom is becasue the ECU starting reading the data from bottom up, the start of the file is the essentially at the end of the proms address range. ie. FFFF

That is why we need to do this to make it work.


Thanks for the explanation. :thumbup:

User avatar
Posts: 6364
Joined: Mon Oct 08, 2012 6:41 pm
Location: Kyneton, Vic

Re: 265 Hemi to efi

Postby vlad01 » Sun Aug 18, 2019 2:10 pm

I went through the same thing when I first started before I really understood how it all worked.

The least I can do is share that in a way that hopefully makes sense.


The other thing I learned that no one mentioned is soldering the EEPROMs directly at least with the genuine SST proms is a bad idea, they are sensitive to the heat and their addressing during burning goes haywire and they die. I had 4/5 die lol, so I now solder a socket first and that allows heat free install of the proms and I haven't had an issue since.
I'm the director of VSH (Vlad's Spec Holden), because HSV were doing it ass about.

Posts: 727
Joined: Tue Apr 21, 2015 1:42 pm

Re: 265 Hemi to efi

Postby heff0018 » Sun Aug 18, 2019 2:35 pm

vlad01 wrote:I went through the same thing when I first started before I really understood how it all worked.

The least I can do is share that in a way that hopefully makes sense.


The other thing I learned that no one mentioned is soldering the EEPROMs directly at least with the genuine SST proms is a bad idea, they are sensitive to the heat and their addressing during burning goes haywire and they die. I had 4/5 die lol, so I now solder a socket first and that allows heat free install of the proms and I haven't had an issue since.

Cheers, ithe eprom was such a tight fit that I guessed it wouldn’t need soldering. Got that part right.

User avatar
Posts: 6364
Joined: Mon Oct 08, 2012 6:41 pm
Location: Kyneton, Vic

Re: 265 Hemi to efi

Postby vlad01 » Sun Aug 18, 2019 3:40 pm

They were soldered from the factory but its a reflow process so the heat is minimal and UV EPROMs are much more hardy. I've never killed one of them.

relying only on the contacts in the memcal might cause issues running as vibration could cause reading issues during operation and throw up errors. The memcal socket isn't a true socket, its meant to be soldered. That is why I solder in a real machined socket and then install the EEPROM into that.
I'm the director of VSH (Vlad's Spec Holden), because HSV were doing it ass about.

Posts: 727
Joined: Tue Apr 21, 2015 1:42 pm

Re: 265 Hemi to efi

Postby heff0018 » Mon Aug 19, 2019 11:44 am

Yep, I soldered in the socket. Cheers

User avatar
Posts: 9788
Joined: Sat Feb 28, 2009 9:05 pm
Location: Tenambit, NSW

Re: 265 Hemi to efi

Postby Holden202T » Mon Aug 19, 2019 2:14 pm

if nothing else its a good idea to socket them so you can put whatever you want in it, if the eeprom fails easy to replace, or if you wanted to burn a finished tune to an eprom then you can and send it on its way.

i've also had some issues with header boards and dodgy connections, having a socket makes it all too easy to pop it out for a read.

User avatar
Posts: 6364
Joined: Mon Oct 08, 2012 6:41 pm
Location: Kyneton, Vic

Re: 265 Hemi to efi

Postby vlad01 » Mon Aug 19, 2019 7:25 pm

Agree for all the same reasons. :thumbup:
I'm the director of VSH (Vlad's Spec Holden), because HSV were doing it ass about.

Previous

Return to Delco ECU Conversions

Who is online

Users browsing this forum: No registered users and 3 guests