Topic: S13 240sx chip tuning thread. (Read 12256 times)

slappynuts · « **on:** April 02, 2009, 10:28:07 AM »

I am going to be tuning some local guys cars so I will work on this thread as it develops. I found a schematic for one of the daughterboards on the net so I drew up the art work for the PCB and will be doing a toner transfer PCB for these.

Towdogg · « **Reply #1 on:** April 02, 2009, 01:20:24 PM »

Cool :somb:

Joseph Davis · « **Reply #2 on:** April 03, 2009, 10:10:55 PM »

Quote from: slappynuts on April 02, 2009, 10:28:07 AM

I am going to be tuning some local guys cars so I will work on this thread as it develops. I found a schematic for one of the daughterboards on the net so I drew up the art work for the PCB and will be doing a toner transfer PCB for these.

I advise you to make the boards for the early S14, with a jumper to select between 32k (S13) and 64k (early S14). The 64K deal is just a couple extra address lines to hit the higher memory area of the chips.

Still need a different board for S14a, tho.

slappynuts · « **Reply #3 on:** April 04, 2009, 07:55:28 AM »

I am going with the simplest things first and then we can move on from there

Joseph Davis · « **Reply #4 on:** April 04, 2009, 08:43:40 AM »

The simplest thing is making one board fit two different types of ECUs, you idjit!

Joseph Davis · « **Reply #5 on:** April 04, 2009, 12:14:07 PM »

How about I reverse this one, it's for either S13 or S14? The guy I bought it from scraped the board maker and chip numbers off, but Joey is not impressed.

slappynuts · « **Reply #6 on:** April 04, 2009, 05:11:04 PM »

What are the part numbers on the chips on the board?

Joseph Davis · « **Reply #7 on:** April 05, 2009, 03:52:16 PM »

Dude scraped them off. Should be a plain old 74HC00 NAND gate and a pair of 74HC373s.

slappynuts · « **Reply #8 on:** April 06, 2009, 02:59:56 PM »

Why did he scrape all that off? Oh well.

I started redesigning my board to use header pins instead of jumper wires to connect to the ecu. I just realized that the ecu is standard space pins.

Joseph Davis · « **Reply #9 on:** April 06, 2009, 04:07:20 PM »

Who knows.

slappynuts · « **Reply #10 on:** April 06, 2009, 07:46:48 PM »

Quote from: Joseph Davis on April 05, 2009, 03:52:16 PM

Dude scraped them off. Should be a plain old 74HC00 NAND gate and a pair of 74HC373s.

Hmm wonder what they are using the latches for? Maybe switching maps? I would have to look a little more at what they do cause im a little weak in that dept ;D

slappynuts · « **Reply #11 on:** April 06, 2009, 07:48:16 PM »

Any idea what size the memory chips that were on it?

Joseph Davis · « **Reply #12 on:** April 06, 2009, 08:35:30 PM »

All of the Nissan daughterboards, and 95% of microcontrollers, use latches to request and "frame" data so the micro can read it off the chip. The micro gives the latch a location on the chip, and the latch sends back the data at that location. Just think of it as an interface.

The S13s (and one S14) ECU have 32 kbyte ROMs (29C256, 27C256, or 27SF512 with the chip burnt to an 0x8000 offset just like we do with Hondas), and the S14s have 64 kbyte ROMs (29C512, 27C512, 27SF512; uses the whole 0x0000-0xFFFF range). NisAnd because I'm an intellectual being, are wierd in how they are structured and need two chips to hold one program... on one daughterboard design the 32 or 64 kbyte is separated into an "even/odd" format where one chip has all the even memory locations and the other chip has all the odd memory locations. Later designs use two chips burned with the normally formatted ROM, for design simplicity, and are more popular due to their being very simple and easy to use. While it is possible to design a single chip daughterboard with a CPLD no one has done so according to Blundar (I don't talk to many people, or roam the internets, anymore so I dunno).

Sir slappy, if you'd like to do the S13 side of things (S14 SR20 is basically identical), I'd be more than happy to fill in with S14 KA24 as it's done a little differently. Frankly, it's a pain in the fucking ass as the fuel map is, in the words of badbiki, "a map of K." If you organise your writeup into a single post, and the daughterboard summary into a single post, while this thread will be a hair messy I can link directly to salient posts in the EM Forum Master Index so the information is easy to retrieve.

slappynuts · « **Reply #13 on:** April 06, 2009, 11:46:46 PM »

Well to be honest with you All I was really planning on doing is S13 because its pretty easy to convert S14 to S14 ecu. The plan was to post up the art work and get people going on their own. I am trying to get something going thats easy enough for people to do toner transfer for the real DIY people or maybe set up a order system online at a production place.

Joseph Davis · « **Reply #14 on:** April 06, 2009, 11:50:16 PM »

I planned on doing a run of them and selling them cheap enough that no one bitches if I make $5.

slappynuts · « **Reply #15 on:** April 06, 2009, 11:51:29 PM »

Same plan ;D

DmC · « **Reply #16 on:** April 08, 2009, 03:20:14 AM »

I did I little digging around and found this link I don't know how helpfull it is but hey it has nissan daughter board info and I think thats what you all are talking about.

http://eccs.hybridka.com/viewtopic.php?f=2&t=29

slappynuts · « **Reply #17 on:** April 08, 2009, 08:41:57 AM »

Thats the same schematic I am using.

HiProfile · « **Reply #18 on:** April 09, 2009, 03:56:49 PM »

Sounds like this would be a perfect candidate for a certain person's "16timer", or 8timer in case of the big roms :yes:

I also have a bin combiner .BAT file that's super easy to use - save with the right file names, and it builds a 4mbit rom. Much cheaper than getting 2 ostriches.

Joseph Davis · « **Reply #19 on:** April 09, 2009, 09:39:46 PM »

I just did an S14 SR20DET today, they are simple as pie. Quite unlike the S14 KA24DE ECUs.

DmC · « **Reply #20 on:** April 10, 2009, 01:33:53 AM »

Quote from: Joseph Davis on April 09, 2009, 09:39:46 PM

I just did an S14 SR20DET today, they are simple as pie. Quite unlike the S14 KA24DE ECUs.

Been reading up on it I think I'm ready to take a crack at one. Now I just need to find someone with a 240 willing to go first.

Joseph Davis · « **Reply #21 on:** April 10, 2009, 10:28:01 AM »

I have some S13 daughterboards that Blundar fronted me, I'll kick you 1-2 at my cost ($25/per) plus $5 ship. They are a beta/prototype run of boards, all tested with A+ operability but cosmetically B-grade since they have an external jumper wire due to design omission.

slappynuts · « **Reply #22 on:** April 10, 2009, 03:36:46 PM »

If you have them already then why am I fucking around? I will take one as soon as I get some money in my paypal. No need to reinvent the wheel.

Joseph Davis · « **Reply #23 on:** April 11, 2009, 12:17:40 AM »

I have 8, and I am keeping at least 4 for myself. If you want the other two I have to spare, same deal as Dennis since you aren't a chump.

DmC · « **Reply #24 on:** April 11, 2009, 06:10:45 PM »

thanks man! I have no money this second but I'll hit you up next weekend.

4speedpride · « **Reply #25 on:** April 20, 2009, 04:49:16 AM »

so i take it that r32 rb20 ecu's already have this daughterboard installed? because about 6 mos. ago i tuned my friend's 240 w/ an rb20 and it was cake. just had to remove the stock chip and reflash another with the tuned maps

Joseph Davis · « **Reply #26 on:** April 20, 2009, 09:41:02 AM »

Never seen that particular ECU, but some of the late 80s early 90s NisAnd because I'm an intellectual being, had proper chips and do not need daughterboards.

slappynuts · « **Reply #27 on:** April 20, 2009, 11:31:40 AM »

There are some odd 8bit ECUs from what I understand.I know the early KA24e ecus are set up like this and some people have done the KA24de retrofits.

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Author Topic: S13 240sx chip tuning thread. (Read 12256 times)