In need of CorComp FDC pics...

[+jedimatt42]

Nope... just did a '.jpeg' just fine...

 

-M@

[+jedimatt42]

There's always tomorrow...

 

You should come back every day

 

-M@

[CantStopClicking]

I think the rules are unique per forum, so that's the 'this community' part... In another thread they mentioned that the development forum has different aging rules for editing...

 

Just throwing questions out there... You're website was built on a MAC, is your mac using .jpeg instead of .jpg? And is atariage stupid about that?

 

-M@

 

Filename is: IMG_6639.JPG (it is from my Mac, but submitted from my PC Interface - FireFox <- the latest crappy version 57.xx)

 

Tried PNG too, same. If I click "More Reply Options" I get some server error.

 

I'll try from my Mac.

 

Thanks for helping, I vaguely remember pulling my hair out trying to attach images last time I was here (year or more).

[CantStopClicking]

Tried from the Mac, same error message.

 

Ok, so can someone walk me through how to attach a picture? (yeah, I feel stupid - and is probably something stupid)

 

In the meantime, I'll just post it to my website. Apologies for the rather lame site right now, I hate web design, but can't afford to have someone else do it. Too many damn hats to wear! lol

 

-Dano

[CantStopClicking]

Another try, from Mac, BUT this time "More Reply Options" actually opened a new and proper window. Yay!

 

 

 

 

[CantStopClicking]

Yeah, it's ugly!

 

And, no, it doesn't work. I received it that way and the person I got it from did not modify it either. So, either it was from the factory that way (I highly suspect) or someone did a hell of a hack job before him. I don't know how or where he got it. At the time, I know he was a member of the Ventura/Oxnard TI-UG.

 

I'm going to plug it in and see what it does. if I remember right, the FDC light comes on solid and that's about it.

 

I will be back (maybe not everyday, but certainly not let a year or two go by in between)

 

-Dano

[CantStopClicking]

Ok, just tested my ugly CorComp "EXP-DCC rev C COMP" board, and yep, solid light on PEB, console turns on to cyan screen, no title bar or video otherwise, no sound, and no response what-so-ever.

 

Dead as a door-nail. Would be kinda cool to fix it though... I was hoping I could at least get to the TI screen and maybe use my CorComp diagnostic cartridge, but no dice.

 

Hmm, maybe I'll try reading in the EEPROM's and see what's in there, and compare those to my working CC-FDC.

 

Speaking of which, in the past couple of years, I finally got my hands on a real chip programmer (vintage of course), but I should be able to program ANYTHING for the TI (or any computer pre-2000's), chip burning wise. if you've got the chip and code, I'll burn it.

 

-Dano

[+Ksarul]

So far, I have not been able to find a schematic for any version of one of the CorComp cards in the wild. What I can tell you, is that the blue capacitors on your board look like they are Tantalum capacitors--which means they are polarized. Normally, based on where they are on the board, these would be .1uF for component isolation. The caps will probably have some numbers/letters on them that would further identify them. Here's a standard calculator for the three-band (the fourth band is the tolerance) resistors used on the board. It might be a good idea to give a good picture of the back of your board too, as that may tell us some more about why they moved the crystal.

[CantStopClicking]

So far, I have not been able to find a schematic for any version of one of the CorComp cards in the wild. What I can tell you, is that the blue capacitors on your board look like they are Tantalum capacitors--which means they are polarized. Normally, based on where they are on the board, these would be .1uF for component isolation. The caps will probably have some numbers/letters on them that would further identify them. Here's a standard calculator for the three-band (the fourth band is the tolerance) resistors used on the board. It might be a good idea to give a good picture of the back of your board too, as that may tell us some more about why they moved the crystal.

 

Do you have a method of trouble-shooting this guy? Component level? I have one of your PEB extender boards to help troubleshoot.

 

I'm pretty sure I have all the electronic tools to solve this, I just don't know how to use them. LOL

 

Voltage measurements? Scope probing? Parts swapping (hate doing that willy-nilly) Other?

 

TIA!

 

-Dano

[+Ksarul]

Other than replacing a couple of defective 9901s, I've never had to do that much with CorComp disk controllers, unfortunately. At some point, I might try and start building schematics for them, but that would also require getting under the chips (with light or by chip removal) to follow the traces there.

[CantStopClicking]

Other than replacing a couple of defective 9901s, I've never had to do that much with CorComp disk controllers, unfortunately. At some point, I might try and start building schematics for them, but that would also require getting under the chips (with light or by chip removal) to follow the traces there.

 

Fair enough. I might help you with that process. I say might, because I hate to *touch* my working CC-FDC, but I'm *more* than willing to teardown the non-functional one - although, I don't know if it would be of any use since it looks so different.

 

What really sucks about these CC-FDC's, is they use the same REV number, yet there are obvious differences on the PCB. Who the heck was running CorComp, and why so sloppy for such a great board?

 

Seems as though anyone from CorComp vanished into thin air, never to been seen nor heard from again. Where-as, just about every other TI guy, has surfaced somewhere, at some point. (sadly a lot from obit's)

 

Anyhow, would me tearing down the dead bastardized CC-FDC be of any value, for schematics?

[Stuart]

One useful test for any faulty card is to check if the DSR on the EPROMs can be read. This is easy if you have a MiniMem cartridge (see http://atariage.com/forums/topic/227990-ti-99-disk-controller-question/?p=3039394) but more difficult if you only have an Extended BASIC cartridge. I've pasted below a short XB program that will read and display the start of the FDC DSR. I've kept it as simple as possible because without a working FDC you're likely to need to type it in by hand! (** NOTE: I've tested this with Classic99 and it works OK, but haven't tested it on real hardware! **)

10 CALL INIT
20 CALL LOAD(12288,2,12,17,0,29,0,2,1,64,0,2,2,48,32,204,177,2,129,64,128,22,252,4,91)
30 CALL LOAD(8196,63,248)
40 CALL LOAD(16376,70,68,67,32,32,32,48,0)
50 CALL LINK("FDC")
60 DIM B(
70 FOR A=12320 TO 12392 STEP 8
80 CALL PEEK(A,B(1),B(2),B(3),B(4),B(5),B(6),B(7),B()
90 FOR L=1 TO 8
100 PRINT STR$(B(L))&" ";
110 NEXT L
120 PRINT
130 FOR L=1 TO 8
140 IF B(L)<32 THEN PRINT "."; ELSE PRINT CHR$(B(L));
150 NEXT L
160 PRINT
170 NEXT A

When you run it, you should get a screen similar to the following, showing lines of 8 bytes of data in decimal then those same bytes as ASCII on the line below. For any FDC, the first four numbers should be 170 (>AA), then a low number or zero, then two zeroes. The data after that varies by type of FDC (the screen below shows the DSR used by Classic99). For a standard TI FDC, you can see the data here: http://www.unige.ch/medecine/nouspikel//ti99/dc1.txt. You can easily look for the device names supported by the DSR ("DSK") in the ASCII part of the listing (to do this for the TI FDC, you'll probably have to change the second number in line 70 from 12392 to 12448 as the device names are further into the DSR, but you'll lose the first couple of lines of results as they'll scroll off the top of the screen).

 

 

 

If the DSR data looks correct and you can see the device names, then the FDC problem most likely lies with the floppy drives, the cable, or the floppy controller or associated circuitry on the card. If the DSR data looks corrupt (and you're absolutely sure you typed the program in correctly!) then you have a more basic problem with the console unable to read the EPROMs or the EPROMs are corrupt, and no messing with the floppy drives or cable is going to help.

 

[Jt - I replied to your e-mail but haven't heard anything back from you.]

Edited January 9, 2018 by Stuart

[CantStopClicking]

One useful test for any faulty card is to check if the DSR on the EPROMs can be read. This is easy if you have a MiniMem cartridge (see http://atariage.com/forums/topic/227990-ti-99-disk-controller-question/?p=3039394) but more difficult if you only have an Extended BASIC cartridge. I've pasted below a short XB program that will read and display the start of the FDC DSR. I've kept it as simple as possible because without a working FDC you're likely to need to type it in by hand! (** NOTE: I've tested this with Classic99 and it works OK, but haven't tested it on real hardware! **)

 

In my case, computer won't even start. However, I can dump the ROM's with my chip burner and see what comes out of that.

 

Do you think the trick with turning on the PEB, after the console, work? I can test this theory later, for grins. But I'll trust my chip burner dump over a software one any day.

 

Cheers!

[Stuart]

 

In my case, computer won't even start. However, I can dump the ROM's with my chip burner and see what comes out of that.

 

Do you think the trick with turning on the PEB, after the console, work? I can test this theory later, for grins. But I'll trust my chip burner dump over a software one any day.

 

Cheers!

 

I don't think the XB program will work in that case unless you have 32K RAM in the console - ISTR that the XB CALL INIT won't work unless 32K RAM was available at boot time. But if you have a MiniMem cartridge you can use the MiniMem trick referenced in the link, or if you have one of the 64/128K ROM cartridge boards then burn my Mini Memory Line-By-Line Assembler, TIBUG and Disassembler cartridge (http://www.stuartconner.me.uk/ti/ti.htm#minimem_lbla_tibug_disassembler_cartridge) and use TIBUG instead of the MiniMem EasyBug.

[pcoderdude14]

Hey All! :-)

 

Well...I tried both; The Mini-Memory "trick" and the XB "trick". Both worked!...for my "functional, no-problem-at-all" TI FDC... with the CC FDC, ...nothing worked. I tried the Mini-mem test first...didn't even light up the LED on the card , when I did "C1100 1"...

With the XB, I just kept getting error notifications, every time I tried to run the program.

So...I'm guessing it IS the circuitry of the CC FDC that is completely unuseable. I was truly wondering if anyone has seen this kind of "Mod" before, in a CC FDC ?

 

Sincerely...

 

Jt

[Stuart]

Hey All! :-)

 

Well...I tried both; The Mini-Memory "trick" and the XB "trick". Both worked!...for my "functional, no-problem-at-all" TI FDC... with the CC FDC, ...nothing worked. I tried the Mini-mem test first...didn't even light up the LED on the card , when I did "C1100 1"...

With the XB, I just kept getting error notifications, every time I tried to run the program.

So...I'm guessing it IS the circuitry of the CC FDC that is completely unuseable. I was truly wondering if anyone has seen this kind of "Mod" before, in a CC FDC ?

 

Sincerely...

 

Jt

 

What XB error did you get with the CC card? Even if the card is duff, I would expect the XB program to still run but return a load of 0 values.

 

Is the function of the DIL switches documented anywhere? I would have expected the MiniMem trick to be able to switch on the card LED (as you say it blinks when trying to access the floppies from BASIC) unless one of the DIL switches is changing the CRU address away from the standard >1100 for an FDC card. You might want to try the MiniMem trick again but try different addresses C1000, C1100 (you tried that already), C1200, C1300, C1400 up to C1F00 and see if any of those light the LED.

 

I wouldn't be too worried about the mod to the crystal yet. The crystal only provides a clock for the floppy controller IC, let's see if we can read the EPROMs first.

Edited January 11, 2018 by Stuart

[atrax27407]

If you get to the point where you need some new EPROM DSR chips, FYI I have both originals and MG upgrades.I also have a mod that removes DSK4 permanently (if you have a RAMdisk designated as such).

[RickyDean]

There are some pictures and some information floating at the following location:

 

http://atariage.com/forums/topic/246297-corcomp-9900-disk-controller-problems/page-5?hl=corcomp#entry3854864

 

I haven't gotten my card functional yet, but did get it to go to the title screen. Beside the eprom on mine there were some jumper pins, broken and disheveled, and the jumper was missing. I tore the board down and planted sockets everywhere and replaced the pins and after much searching discovered the jumper needed to be on the bottom two pins for the title screen to come up, before I was just getting a cyan screen.

Edited January 11, 2018 by RickyDean

[pcoderdude14]

Hey All! :-)

 

Well...you guessed it right, Stuart. The card is "Duff" (I am not sure exactly what that means, btw )...for the most part, I get only ONE "blink" when I try to access the CC FDC thru BASIC, xb, or even, a "cat"alog command.

There was nothing but ZEROS, and, DOTS, when I tried that XB program, and, I will try the minimem "trick" again, but, I was wondering if I should go "bare minimum" on what is in the P-Box, when I try various other "DSR"

viewing commands? Won't that "contaminate" the other cards...(ie. RS232, 32k, ect...).

I really liked the XB command,...I have never seen a XB program with SOOOO MANY "CALL LOAD" FIGURES...

I was reading a little in the Mini-Memory Flyer/Brochure about how to do "DSRLNK" commands...is there anyway to RE-write that XB program in ASM? Or, would the DSRLNK's be available for use, in XB?

 

Still pretty new at this level (DSR) of coding/programming for the Ti99 , so please, bear with me and my ignorant questions.

 

Jt

[pcoderdude14]

 

What XB error did you get with the CC card? Even if the card is duff, I would expect the XB program to still run but return a load of 0 values.

 

Is the function of the DIL switches documented anywhere? I would have expected the MiniMem trick to be able to switch on the card LED (as you say it blinks when trying to access the floppies from BASIC) unless one of the DIL switches is changing the CRU address away from the standard >1100 for an FDC card. You might want to try the MiniMem trick again but try different addresses C1000, C1100 (you tried that already), C1200, C1300, C1400 up to C1F00 and see if any of those light the LED.

 

I wouldn't be too worried about the mod to the crystal yet. The crystal only provides a clock for the floppy controller IC, let's see if we can read the EPROMs first.

Hey again...

 

Forgot to mention...

The DIL switches are for "speed"/"seek rate" for the heads of the drives being used with the FDC. That's all they do, from what I understand. I have always wondered how come CorComp didn't put in more jumpers and switches for other areas, like CRU-picks, or, even for trying to do "power level" alternatives!?!

 

Jt

[Stuart]

 

There was nothing but ZEROS, and, DOTS, when I tried that XB program, and, I will try the minimem "trick" again, but, I was wondering if I should go "bare minimum" on what is in the P-Box, when I try various other "DSR"

viewing commands? Won't that "contaminate" the other cards...(ie. RS232, 32k, ect...).

 

 

Yes, take everything else out of the PBOX before trying to access the card at other addresses.

[pcoderdude14]

Hey there, All! :-)

Good News. When I tried the CRU address >1000, The FDC card light came on, and, stayed on like the BEST Christmas tree lights I've ever seen!!!

 

I tried the XB program again, too...and, still just "0"'s and "DOTS"....but, now, at least, I have something that tells me the card is , at the very least, being "seen" by the console.

 

I have a socket, on one of the EPROMs that is in need of fixing. It is partially "cracked" on an edge, and, about 2-3 pins on the EPROM is , basically, NOT socketed.

I tried a quick fix, with this, ...just using some scotch tape to try and make the "contact" between the EPROM pins and the socket, but, it looks as though I am going to have to

REsolder the socket.

Which brings me to a new topic: Why are there sockets in the CC FDC, and, further...why didn't they (Corcomp) socket ALL the ICs, instead of just socketing a few? Did they

expect (some) of these ICs to fail?

The sockets that I have on my FDC look as though they have ALWAYS been there, ...not because of modification. So is this the way the Corcomp FDCs came from the factory?

 

 

 

Jt

[Stuart]

Hooray, some progress!

 

If the card is at CRU >1000, then try the XB program again but in line 20 change the *fourth* number from 17 to 16 (this number determines which CRU address is accessed). When you run the XB program the LED on the card should flash - but it may be so brief that you don't see it.

 

If you've got a bad EPROM socket then that is very likely to be the problem. You may well find that it bursts into life when the socket is repaired/replaced.

 

Looking at which ICs are socketed, you've got the EPROMs and PALs that will be programmed and fitted to the card after it has been manufactured, and the 9901 and FDC which, although not *expected* to fail, are perhaps the most likely to have failed if the card develops a problem. And/or fault-finding a hardware problem on the card is easier if these ICs can be removed (without damaging them).

[atrax27407]

There were several iterations of the EPROMs (and probably the PALs as well). If there are, in fact, several distinct revisions, if the schematic changed so would the PAL equations. Future design changes are likely why some of the chips are socketed and others are not.

[pcoderdude14]

Hey All! :-)

 

Hooray, some progress!

 

If the card is at CRU >1000, then try the XB program again but in line 20 change the *fourth* number from 17 to 16 (this number determines which CRU address is accessed). When you run the XB program the LED on the card should flash - but it may be so brief that you don't see it.

 

If you've got a bad EPROM socket then that is very likely to be the problem. You may well find that it bursts into life when the socket is repaired/replaced.

 

Looking at which ICs are socketed, you've got the EPROMs and PALs that will be programmed and fitted to the card after it has been manufactured, and the 9901 and FDC which, although not *expected* to fail, are perhaps the most likely to have failed if the card develops a problem. And/or fault-finding a hardware problem on the card is easier if these ICs can be removed (without damaging them).

 

First off , .. I didn't get anything but "Zeros" and "Dots" again, with the number-change in line 20. :-( Also, I should mention that , just out of curiosity , I tried different "C>" numbers with the CC FDC ...oddly enough, all the EVEN numbers I tried --->(C>1000, C>1200, C>1400...)upto C>1700 made the FDC turn on (Lit the LED). Does anybody have a reason why this would happen. I couldn't figure out , and, my only other IDEA is to try doing the (C>____) numbers WITH other cards, that would have CRU addresses in the realm of >1000 to >1700 in the PBox at the same time with the FDC, and, see if the FDC AND other cards "light up" at the same time?

This might be dangerous, I am thinking...so I thought I would ask you guys if this IS or IS NOT a good idea?

 

Sincerely,...

 

Jt