Eeprom/pic Burner

[Raster]

I havent talked here in a while, but I have a pritty good Idea.

I though of a TI calculator EEPROM burner, can burn and read 2 Mbit EEPROM's. Then while I though of this topic I'm making, what about PIC's too. I just wanted to see if this would be a good idea to build.

PS: I know Ill have to have external memory for this project, and another power source for the 12.5V to burn the EEPROM.

And if you have any other ideas post'em.

[Raster]

Wow. The last time I was here there was alot more action going on in these forums. WHAT THE H*** HAPPEND!!! Sorry for the languedge. .

[AlienCC]

I'm afraid a lot of people got frustrated by the slow load times we had with the old hosting service, this is no longer a problem so feel free to invite anyone to come participate.

--AlienCC

[DigiTan]

You were probably last here what that agility guy went spam-crazy on everybody so he could get his 1,300 posts.

Well, you could definately reprogram one if you could get around the problem of a TI only having 2 link lines. You could probably "parallel-ize" the bits using some kind of high-speed shift register like a 74HC194 chip or even a PIC. Atmel Corp. specializes in In-System Programmable memory, which might be just what the doctor ordered. That way you could actually use your calculator as a field programmer/reprogrammer. Maybe even reprogram consumer products that already exist!

PICs I'm not certain about, but I've heard rumors that some 8051-family chips have built-in bootloaders that let you program the entire chip through just a 3-wire cable, with no other annoying equipment. Plus, that software is factory-installed, so it's always 'good to go.' An advanced PIC might also have this feature.

Anyway, an EEPROM/PIC programmer would be a neat alternative to the $100 or $200 programming boards. And these kinds of things always look good on the resume!

[Raster]

I was thinking about using a 74HC164 8 bit parallel out serial shift ( 2 hooked together so I can have 12 bits explain later), and a 74HC165 serial out 8 bit parallel shift.

I want 12 bits so I can have 8 bit data to communicate between the EEPROM burner and the calculator, and the rest of the 4 bits the request bits from the calculator (ex. set address, set data, read, write).

It going to be based off of The Rich Files SPin Terface cartredge. (Well a few ideas from it.)

I was also thinking of an LCD Display to go along with it, to tell what Adress is being written, read, and so on. But I think Im going a little to far with that .

Ill have some flow charts (or what ever they are called too show the logics of the design) posted soon.

PS: Im 15, so I dont know what everything is called. .

[Raster]

I just had another idea. This could be the key to playing old gameboy games (the black and white ones) on a TI Calculator.

[DigiTan]

Oh yeah, heh I guess I forgot to ask wheter your EEPROM was serial or parallel.

Well, 74HC164 is an excellent choice. Plus, it's one of the only ICs Radio Shack still sells in every store.

Character LCD is just as doable. There is a very popular LCD standard called "Hitachi HD44780" that tells you how to send characters to the screen, move the cursor, make the cursor blink, and do all sorts of other things. You could add on to your calc burner using just 6 data lines (4 for data, 2 for commands). LCD number displays are a little less standardized, but also doable.

Anyway, it's cool you're doing this stuff a only 15. Most enginners I know don't attempt to do these things solo until well into college or grad school.

[Raster]

Man thats funny, I just pulled out an LCD display out of a laser printer, that has a Hitachi HD44780A00 (japanies character map) controller not to resent I though about using that. What are the odds of that . Well, I have school tomarrow (today ), so I am going to think about how Im going to do this.

And about the serial EEPROMS, I have no clue how they work, I've heard of them though. Is there a good site to start out with that will teach me more about serial interfacing? (I have a basic understanding)

[Arcane Wizard]

[DigiTan]

Basically, serial will use the same rules as parallel, but it will also receive flag bits from you, so it will know if you're sending a command, an address, or plain old data.

The serial rules vary from company to company, so if you had a particular chip size in mind, you could search Atmels site for App Notes. Most app notes include (very optimised) source code so that's always a plus too.

[Raster]

I finaly have a schematic done, took a while, but its done.

And while I was making the schematic, I thought of many more posibilitys (some will be listed that I have already posted):

Old black and white GameBoy cartrage reader
(E)EPROM Burning (of course)
External Memory expantion, without PIC controller
Possible PIC Burning

I also have some specs of the EEPROM burner:
2-4 Mbit RAM memory
RAM to ROM data transfer
ROM to RAM data transfer
RAM to calc data transfer
clac to RAM data transfer
LCD interface (work in progress)

Well, finaly the schematics!!!
TI-EEPROM Burner page 1
TI-EEPROM Burner page 2
Not the best, If you have a problem with size or format, just tell me and I'll fix it.
If you find any problems in the schematic, again tell me.

Happy days .

[DigiTan]

Looks pretty solid to me. I don't have the all component specs on me right now, but all the busses look about right. If you want Schematic/PCB software, you can get the lite edition of CADsoft EAGLE for free. It even does auto-routing for you! If all your parts aren't on Eagle already, you can probably download it at from the Eagle archives.

[Raster]

Bad news, I got in troble from my parents, because I got an F in english , so I will not be here for a week or two, I probably will be here tommarow to answer the last of the questions, but that will be it, so post as many questions as possible.

[DigiTan]

Aw, man. That's bad. Well, if I got grounded a week for every time my engineering got in the way of school, I'd be serving a life sentence. Heh heh. A little humor there. Well, I hope your parents go easy on you. I'll give the EEPROM burner another look-over and hopefully help get it off the ground.

[Raster]

Ok, I'm going to be out for only 5 days, so Ill seeya saturday or sunday .

[Raster]

Yes, I have been out for the past 2 weeks, both from procrastinating, and lack of supplys I will not have my prototype done in a while. I just thoug I would give you an update of whats going on. (Hehe, Im on my school's computers, got passed the firewall )

[Weregoose]

[Raster]

I have decided, that I will continue this project of mine. I have been bored lately, and I havent touched a soldering iron for a couple of months. So here is a good oppertunity for me to mess around. Now all I gota do is find those schematics again, that were in my closet .

[EDIT]

I found the schematics, and they aint pretty :hmpf: .