TI-99/4A "insert cartridge" message

[TheRealAnubis]

Hi,

I just swapped out all 8 RAM IC's with sockets and new RAM, now when I power on, I get the intro screen, I press a key and it gives the message "Insert Cartridge". Any cartridges that I have tried do not work - the screen goes crazy after the intro screen.

I understand that the message to insert the cartridge relates to GROM 0 (I read that if you remove GROM 0 you get this message). Anyone have a source for these, and if that's bad, shouldn't the cartridges still work?

Thanks!

Edited June 12, 2014 by TheRealAnubis

[Gary from OPA]

Grom 0 is working as your title screen appears.

 

But Grom 1 and 2 is your TI Basic if that is missing or not working then 'insert cartridge'

 

But if no cartridges are working, it could be your 'new ram' is still not perfect.

[TheRealAnubis]

Hmmm... I'll check that out. Thanks!

[Retrospect]

29 years and this is the first time I ever knew the TI did that.

 

Good in a way, it's programmed in ROM not to simply crash or lock up on not finding anything in it's path.

[TheRealAnubis]

Ok,

 

I ended up having several problems that combined to make this happen -

 

Cartridge port - that little foam insert that used to be there has deteriorated and turned into a sticky mess - this stuff was on the cartridge and in the port. Cleaned.

Cartridge port on motherboard - had some green oxidation on several of the pins. Cleaned.

GROM 1 & 2 - had a brownish oxidation on the pins. I used my brass brush on both of them and now the problem as cleared up!

 

Now my only problem is non-working A,S,D,F,G keys. It's the switch type keyboard, and I sprayed the non-working keys with some contact cleaner, but they are still dead. I'm going to make sure that the cable that connects to the motherboard doesn't have any breaks or tears as advised in another post.

[Asmusr]

 

Generated from Js99er by disabling GROM 1+

[+OLD CS1]

I remember back in the day when K-Mart had 99/4As on display. At our store the console would show this. I assume they made special models for display which lacked the TI BASIC GROMs and would just play games?

[RobertLM78]

I remember back in the day when K-Mart had 99/4As on display. At our store the console would show this. I assume they made special models for display which lacked the TI BASIC GROMs and would just play games?

Nice flashback . I can just barely remember getting some carts with my mom at Sears.

[Ed in SoDak]

I had a console with one or more bad RAM chips. Like the OP, I removed all of them, socketed the board and installed new replacement chips. After all that, it still didn't fire up and I never did track down the problem. I still have the console stored away, it seemed a shame to waste all the work and parts.

 

My answer to that setback was to stock up on spare consoles. I think I have 5 now; that one, another dead one and three still working. Two basic PE boxes with multiple floppy drives, plus speech and EXB for each. Back when I used it to handle my darkroom print processing, a working and reliable TI was literally indispensible! Not to mention helping with the books and officework, plus all the after-hours "fun" stuff I did with it.

 

Glad you got yours running! My first thought would have been to check for bad solder joints or bridges on all those socket pins. I gotta also wonder if those other problems you found weren't part of the fail that caused you to replace the RAM in the first place?

 

"A,S,D,F,G" Aren't these keys all tied to a common matrix connection? In which case, a simple keyswitch cleaning won't help (but can't hurt). The key layout is easy enough to find. Either a bad trace or perhaps a blown diode on that line? Spare keyboards are no problem to find if that's the easy cure.

-Ed

Edited June 13, 2014 by Ed in SoDak

[Gary from OPA]

I myself got a TI99 console with bad video ram, got to do the same thing, any good sources for those video ram dram chips?

[+OLD CS1]

I myself got a TI99 console with bad video ram, got to do the same thing, any good sources for those video ram dram chips?

 

An F18A?

[RobertLM78]

 

An F18A?

That will do the trick .

[TheRealAnubis]

I myself got a TI99 console with bad video ram, got to do the same thing, any good sources for those video ram dram chips?

You can order them new at Jameco - .89 each if you buy 10 or more (.99 if you don't). There is also a guy on ebay selling working pulls for a good price too if you can get people to NOT bid on them!

Edited June 13, 2014 by TheRealAnubis

[TheRealAnubis]

I had a console with one or more bad RAM chips. Like the OP, I removed all of them, socketed the board and installed new replacement chips. After all that, it still didn't fire up and I never did track down the problem. I still have the console stored away, it seemed a shame to waste all the work and parts.

 

My answer to that setback was to stock up on spare consoles. I think I have 5 now; that one, another dead one and three still working. Two basic PE boxes with multiple floppy drives, plus speech and EXB for each. Back when I used it to handle my darkroom print processing, a working and reliable TI was literally indispensible! Not to mention helping with the books and officework, plus all the after-hours "fun" stuff I did with it.

 

Glad you got yours running! My first thought would have been to check for bad solder joints or bridges on all those socket pins. I gotta also wonder if those other problems you found weren't part of the fail that caused you to replace the RAM in the first place?

 

"A,S,D,F,G" Aren't these keys all tied to a common matrix connection? In which case, a simple keyswitch cleaning won't help (but can't hurt). The key layout is easy enough to find. Either a bad trace or perhaps a blown diode on that line? Spare keyboards are no problem to find if that's the easy cure.

-Ed

Sounds like a good setup! I've only got one working out of the 4 I have. I did check the RAM that I pulled, and only one was dead. Well, at least it's all socketed now so I can just pop them out if they die!

 

You are correct on the connection - I found a 'surgery' page here:

 

http://nouspikel.group.shef.ac.uk/ti99/surgery.htm

 

This led me to double check the wires from the plug to the keyboard, and wire 3 was actually broken where it connected to the plug! The wire was still 'connected' for all appearances - so without a meter you would have never guessed it to be bad.

 

The info I used was:

 

 

The keyboard connection cable is fairly fragile. If one of the wires gets loose you will notice that a whole row or column of key stops responding. Refer to the following matrix to find out which wire is damaged (the red wire is #15):

Key Wire

= . , M N / #5

space L K J H ; #4

enter O I U Y P #1

9 8 7 6 0 #2

fctn 2 3 4 5 1 lock #7

shift S D F G A #3

ctrl W E R T Q #10

X C V B Z #11

#12 #13 #14 #15 #9 #8 #6

In other words:

1 Keyboard row 2 (enter O I U Y P)

2 Keyboard row 3 ( <nc> 9 8 7 6 0)

3 Keyboard row 5 (shift S D F G A)

4 Keyboard row 1 (space L K J H ; )

5 Keyboard row 0 ( = . , m n /)

6 Keyboard alpha-lock key

7 Keyboard row 4 (fctn 2 3 4 5 1 alpha_lock)

8 Keyboard column 5 ( / ; P 0 1 A Q Z)

9 Keyboard column 4 ( N H Y 6 5 G T B)

10 Keyboard row 6 (ctrl W E R T Q)

11 Keyboard row 7 (<nc> X C V B Z)

12 Keyboard column 0 (= space enter <nc> fctn shift ctrl <nc>)

13 Keyboard column 1 (. L O 9 2 S W X)

14 Keyboard column 2 (, K I 8 3 D E C)

15 Keyboard column 3 (M J U 7 4 F R V)

 

I like to post this kind of stuff because someday that page may not be available, then you will just hit a dead link and never get the info...

 

There is a TON of TI information on those pages...

 

I hope this helps the next traveler looking for keyboard information.

 

As for my other keyboards - one confirmed dead, even after cleaning. It's a Mitsumi, and only 4 or 5 keys work on that one. Also, I did check the cable - they are all connected!

 

Thanks for the help everyone!

Edited June 13, 2014 by TheRealAnubis

[Ed in SoDak]

Sounds like you're on your way! Good job tracking down a wire broken inside the insulation. Rare, but it does happen. Odd you have so many dead keyboards. I always thought they were pretty sturdy, but there were cheaper ones that TI used later on.

-Ed

[TheRealAnubis]

Sounds like you're on your way! Good job tracking down a wire broken inside the insulation. Rare, but it does happen. Odd you have so many dead keyboards. I always thought they were pretty sturdy, but there were cheaper ones that TI used later on.

-Ed

 

Yeah, overall I'm not having very good luck getting them going. The one I have working I'm pretty happy about, though!

[Tursi]

Sounds like you're on your way! Good job tracking down a wire broken inside the insulation. Rare, but it does happen. Odd you have so many dead keyboards. I always thought they were pretty sturdy, but there were cheaper ones that TI used later on.

-Ed

 

Yeah, I have a whole box of NOS Mitsumis with the membrane contacts, and as far as I've seen so far, every single one I've pulled out barely responds. I haven't dismantled them to see if they can be fixed, but seems likely that oxidation is a bigger problem than on the older mechanical switches.

[TheRealAnubis]

 

Yeah, I have a whole box of NOS Mitsumis with the membrane contacts, and as far as I've seen so far, every single one I've pulled out barely responds. I haven't dismantled them to see if they can be fixed, but seems likely that oxidation is a bigger problem than on the older mechanical switches.

 

It's a strange setup inside.. There's a sticky plastic cover that can be gently peeled off, which I did, then I used alcohol to clean everything, and it didn't make a bit of difference..

[Ed in SoDak]

Might be a job for DeOxit, as that will chemically remove oxidation which alcohol alone won't cut. I always used a pencil eraser, but then you have the rubber eraser crumbs in the mix, so that probably would do more harm than good.

 

Probably far easier to get a "real" TI kbd with mechanical switches.

-Ed

[CantStopClicking]

I like to post this kind of stuff because someday that page may not be available, then you will just hit a dead link and never get the info...

 

There is a TON of TI information on those pages...

 

I hope this helps the next traveler looking for keyboard information.

 

As for my other keyboards - one confirmed dead, even after cleaning. It's a Mitsumi, and only 4 or 5 keys work on that one. Also, I did check the cable - they are all connected!

 

Thanks for the help everyone!

 

Thanks for posting the trouble-shooting tips. I've always wanted to put together something that had all the tips like this combined in one spot but that's not anywhere near my list of things to do yet. Google is the best bet so far. So posting your findings for future reference is definitely a good thing in my book!

 

I believe there was a post on the Yahoo forums (long ago) that someone who worked for TI, and did repairs, had done a write up on specifically, and extremely detailed, of how to repair the keyboard. Of course, there were many types and he probably was dealing with TI models but the concept should still apply. I can't remember where I saw it but I think it was the 4A group on Yahoo.

 

Cheers!

 

-Dano