Jump to content
IGNORED

HFDC Problem


CosmicBoy
 Share

Recommended Posts

Hi everybody,

 

is someone out there who can repair a HFDC controller or can give some advice.

 

After a long time i tried to reactivate my Geneve, but i cannot boot from a floppy using my hfdc.

Booting with a TI Floppy-Controller is no problem.

 

The disk-drive stops after a few seconds and the LED of the hfdc is flashing.

 

i made a video, but i think its to big for uploading here.

 

 

Link to comment
Share on other sites

Well that's a bummer. The only reason I asked is the hfdc does not not "wake up" right away with no mfm hard drive attached. It takes it over a minute to look at a floppy so I'm told. There is a mod that forces the hfdc to look for a floppy right away, I've done this simple mod with switch to both cards that I own. I do not have the technical expertise to fix yours if it has a problem. There are a couple of guys here that are hardware gurus, hopefully they'll see this post and give some help.

  • Like 1
Link to comment
Share on other sites

Hi everybody,

 

is someone out there who can repair a HFDC controller or can give some advice.

 

After a long time i tried to reactivate my Geneve, but i cannot boot from a floppy using my hfdc.

Booting with a TI Floppy-Controller is no problem.

 

The disk-drive stops after a few seconds and the LED of the hfdc is flashing.

 

i made a video, but i think its to big for uploading here.

 

 

 

If comfortable doing so, snap a few pictures of the HFDC - front and back - outside of its clamshell. This will help determine the upgrade state of the card and the DIP settings.

 

1. Does the card have a clamshell? The HFDCs rock in the PEB without it, making it prone to shorting out the card.

2. When the LED flashes at the end of the boot attempt, is it normal brightness or dimmed? Are any of the disk drive lights illuminated or motor running?

3. You said you tried both hard drive and floppy. Were both connected -and- powered up? Some controllers cannot function if one or the other is turned off and connected. (this points to a problem with the LS240 and LS374 buffers).

4. Which of the connected devices are terminated with a terminating resistor? This is also important. Be sure the hard drive's terminating resistor(s) are inserted. Some drives will have two SIP resistor networks; be sure both are in place.

5. What other cards are in the PEB?

 

Edit: added question 5 and a few other comments.

Edited by InsaneMultitasker
Link to comment
Share on other sites

 

If comfortable doing so, snap a few pictures of the HFDC - front and back - outside of its clamshell. This will help determine the upgrade state of the card and the DIP settings.

 

1. Does the card have a clamshell? The HFDCs rock in the PEB without it, making it prone to shorting out the card.

2. When the LED flashes at the end of the boot attempt, is it normal brightness or dimmed? Are any of the disk drive lights illuminated or motor running?

3. You said you tried both hard drive and floppy. Were both connected -and- powered up? Some controllers cannot function if one or the other is turned off and connected. (this points to a problem with the LS240 and LS374 buffers).

4. Which of the connected devices are terminated with a terminating resistor? This is also important. Be sure the hard drive's terminating resistor(s) are inserted. Some drives will have two SIP resistor networks; be sure both are in place.

5. What other cards are in the PEB?

 

Edit: added question 5 and a few other comments.

 

1. no it is not but i am using karsul testboard(?) - so the card is outside of the box.

2. the led is dimmed, the disk drives light is off, the motor stops, the geneve stops working

3. i tried both, powered up and powered off - also tried only floppy and only disk drive

4. i am not sure if any of the drives is terminated.

5. there are no more cards in the box

 

as far as i can remember everything is working a few years ago. right after that the system has

been stored in my apartment and after i moved to my new house it has been stored in the basement a few month.

 

 

 

 

 

post-34615-0-60030600-1452459199_thumb.jpg

post-34615-0-24824700-1452459239_thumb.jpg

WP_20160110_18_03_14_Pro.mp4

Link to comment
Share on other sites

 

1. no it is not but i am using karsul testboard(?) - so the card is outside of the box.

2. the led is dimmed, the disk drives light is off, the motor stops, the geneve stops working

3. i tried both, powered up and powered off - also tried only floppy and only disk drive

4. i am not sure if any of the drives is terminated.

5. there are no more cards in the box

 

as far as i can remember everything is working a few years ago. right after that the system has

been stored in my apartment and after i moved to my new house it has been stored in the basement a few month.

 

 

Check the voltage coming out of your two 5v regulators (one in front, one in back). The regulators appear to be the original parts. The capacitors are not original, so someone serviced the card at one time. I am fairly certain this card never passed through Cecure Electronics as the regulators and QIC02 parts are stock. ;)

 

Omega's post shows what looks like leftover flux or tape residue. The bottom chip is part of the QIC-02 circuit. It usually has little to no impact to the card's operation. You can reflow the solder, just be sure not to short the leads to adjacent points or traces. Be aware that removing the QIC02 chips requires adding a jumper to the back of the board. The top chip is the DSR RAM. If it has bad solder spots, it could affect card operation. You might also want to carefully reseat the DIP chips since you had this card in storage.

Edited by InsaneMultitasker
Link to comment
Share on other sites

Hi CosmicBoy. I would love to help, but I fear I don't have the skills.

The HDFC can be used with the TI-99 as well, so maybe you can exclude the Geneve as source of the problem if connecting a standard TI-99 to your PEB.

Remove as many cards as possible. So just the Flex Interface, the HDFC and try if anything shows when turning it on.

I also have two HDFC controllers and can do comparison Tests, however no Geneve here.

Grüße, Klaus (Vienna)

  • Like 1
Link to comment
Share on other sites

I have had to replace some of the SMC chips to get both of mine functioning, and back in the day, I had removed everything from each board and soldered on sockets to make removal and replacement of the chips easier. Had a problem though with some pulled pads on one, so traced down the circuit paths and soldered in wire to complete the circuit. This is something I now have to do again, because, in storage the wire(s) have been broken from their solder points. These may be things you will have to look at.

Link to comment
Share on other sites

 

arghh .... ich checked the 12V and 5V regulators in front yesterday ... and forgot the rear one :(

i check that later.

Sounds good. Test at least twice: once when you start the system, once after the failure. If the regulator is bad and if it hasn't started to drop voltage, you could be lulled into a false sense of "everything is ok".

 

You probably know this already : be careful when testing the voltage. If you accidentally short the ground and the input (8v or more) together with the test lead, bad things can happen.

Link to comment
Share on other sites

The HDFC can be used with the TI-99 as well, so maybe you can exclude the Geneve as source of the problem if connecting a standard TI-99 to your PEB.

Remove as many cards as possible. So just the Flex Interface, the HDFC and try if anything shows when turning it on.

I also have two HDFC controllers and can do comparison Tests, however no Geneve here.

 

 

I already tried this and the Geneve boots with a standart TI Controller.

 

Sounds good. Test at least twice: once when you start the system, once after the failure. If the regulator is bad and if it hasn't started to drop voltage, you could be lulled into a false sense of "everything is ok".

 

You probably know this already : be careful when testing the voltage. If you accidentally short the ground and the input (8v or more) together with the test lead, bad things can happen.

 

The regulators are ok. both 5V regulators put 5,2 out.

I noticed that the u22 socket is empty - is this normal ?

 

I think i replace the capacitors.

 

I have had to replace some of the SMC chips to get both of mine functioning, and back in the day, I had removed everything from each board and soldered on sockets to make removal and replacement of the chips easier. Had a problem though with some pulled pads on one, so traced down the circuit paths and soldered in wire to complete the circuit. This is something I now have to do again, because, in storage the wire(s) have been broken from their solder points. These may be things you will have to look at.

 

i check that a the weekend, thanks for the hint.

Link to comment
Share on other sites

 

I already tried this and the Geneve boots with a standart TI Controller.

 

 

The regulators are ok. both 5V regulators put 5,2 out.

I noticed that the u22 socket is empty - is this normal ?

 

I think i replace the capacitors.

 

 

i check that a the weekend, thanks for the hint.

Yes socket u22 should be empty, I believe it was part of the streaming tape drive logic, that never got implemented into the HFDC. I had an issue were my hdc 9234 chip was bad on the one that has broken wires(found one on ebay, but difficult to find). On the one that is working(haven't tried either with a MFM hard drive as of yet) I had to replace the hdc 9223 chip to write to high density disk( the chip I had in there had a tiny bubble uplifted on it that showed me that part of the logic had blown internally). So repairing them is not easy, but can be accomplished. I believe that kl99 was saying maybe to use a TI99/4a and see if you are experiencing the same problems(if you have one of course).

Edited by RickyDean
  • Like 1
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
 Share

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...