HRD 4000B

[NewcomerTI]

Oh my - I have yet to determine what connection isn’t made on this board.  It has been several long evenings now with no changes in what I thought would be an easy fix - now I’m beginning to think I am missing the DSR or something I didn’t comprehend in reading the construction manual to try and configure this board.  I am trying to really pin out every connection but have not come across any that don’t make sense. 

 

Not sure where to look next - but the other 4000B board works great in playing midi files through the Midi Master & Mini Memory cartridge onto the keyboard arrangement - I might be looking for help if I cannot locate the missing link here. Any other suggestions?

[Gary from OPA]

28 minutes ago, NewcomerTI said:

Oh my - I have yet to determine what connection isn’t made on this board.  It has been several long evenings now with no changes in what I thought would be an easy fix - now I’m beginning to think I am missing the DSR or something I didn’t comprehend in reading the construction manual to try and configure this board.  I am trying to really pin out every connection but have not come across any that don’t make sense. 

Not sure where to look next - but the other 4000B board works great in playing midi files through the Midi Master & Mini Memory cartridge onto the keyboard arrangement - I might be looking for help if I cannot locate the missing link here. Any other suggestions?

I think your cru dip switch block is wrong.

 

From the video it seems you have the card enabled at all crus addresses except for the last position.

 

As that dip switch device is down for off, so all switches should be down except for one.

 

Try switching it around placing only 1 in the upper position.

 

Or replacing it totally with a different type design.

 

If that doesn't work look carefully at all the machine sockets sometimes they can not be making full contact with the 74 chips pins.

Edited June 13 by Gary from OPA

[NewcomerTI]

I tried flipping the switch to the other setting the board isn’t recognized then - only the 1100 disc controller and 1300 rs232 & PIO appear.
 

I’ll look at trying to reseat the 74 chips to see if they are not making contact.  Thanks for the suggestions.
I’m hoping to get this board recognized and configured before too long. It’s already been too long. 

[NewcomerTI]

Replaced the rocker panel switch to be sure there wasn’t any conflict - no change. I double checked the continuity to each pin of the 74 IC’s and there is no ‘open’ pins.

 

I checked over the board again to verify all chips to be oriented correctly, no bent pins, or any abnormalities that I can see.

 

still not recognizing the floppy controller or the RS232 & PIO (lists them as ‘unknown card’ at address 1100 and 1300) unable to load a ROS yet!

 

 

 

[RickyDean]

1 hour ago, NewcomerTI said:

Replaced the rocker panel switch to be sure there wasn’t any conflict - no change. I double checked the continuity to each pin of the 74 IC’s and there is no ‘open’ pins.

 

I checked over the board again to verify all chips to be oriented correctly, no bent pins, or any abnormalities that I can see.

 

still not recognizing the floppy controller or the RS232 & PIO (lists them as ‘unknown card’ at address 1100 and 1300) unable to load a ROS yet!

 

 

 

I may have mentioned this before, I would walk the multimeter leads down the side of each socket. If I found a short at any point, I would look at the schematics for that set of pins to see if it was designed that way, if not, then probably your problem. I would test the whole board this way.

Then if that didn't fix it, If you for some reason remember that you may have used an exacto knife to cut something, then check that(those) area(s) to see if you cut a trace accidently. I did this with one of my Sams cards I built and had to go over it with a fine tooth comb(magnifying system) till I found a tiny slit that I had done to trim down a socket.

Then finally if that doesn't fix it, test each pin front and back for continuity, as I had an IDE card I built and then blew a capacitor I had placed on backwards (it was late night, sleepy excuse). It took out some items when it blew, but also it caused a pin on a tooled socket to crack, creating a break. Shift838 found this for me when he was cheking it out for me. 

 

So carefully look at all areas and test, test, test. If you can't find it. I can look at it for you as I built 4, 2 original and two of @Ksarul's.

Edited June 15 by RickyDean
spelling

[NewcomerTI]

The RS232 and disk controller show up with the RAM card off.

 

Its when the RAM card is on that the page shows that it’s in the ‘system’.

 

I ran the multimeter test down the board to check for a short on the pins but found only the ones that would give me a short from the schematic and board configurations.

The front LED remains on constantly but I was able to run the memory test and it passed with zero errors.

I am still not able to successfully run CFG yet but I know that all the memory is being recognized. I ‘wholesaled’ out all the 74 series chips to see if one was creating this scenario and move the problem but with no change. 
The continuity test from lead side to component side showed ‘good’ connections to all the chips. I’m still looking for a connection not being made from the diagrams and schematic. 
 

Edited June 18 by NewcomerTI

[NewcomerTI]

Just messing with the address switch settings I noticed I cannot configure this RAM card as address 1000 ( both the other RAM cards I own are set that way ) without it behaving erratic - Not sure if this would give a clue as what could be interfering with its ability to go inactive ( no LED on the front staying on solid ) or unable to accept a ROS.  
 

More erratic is I guess a better term for its behavior - it only allows access to the disk controller when the RAM card is switched off - system errors out if trying to run the CFG file from E/A or Running the Load program from Extended Basic when it is in the on position. 
 

I hope this isn’t too confusing but I’m trying to resolve this cards condition and have been listening and attempting any recommendations that come my way!

 

Thank you all for all the help!

 

I appreciate it!

[Gary from OPA]

29 minutes ago, NewcomerTI said:

Just messing with the address switch settings I noticed I cannot configure this RAM card as address 1000 ( both the other RAM cards I own are set that way ) without it behaving erratic - Not sure if this would give a clue as what could be interfering with its ability to go inactive ( no LED on the front staying on solid ) or unable to accept a ROS.  
 

More erratic is I guess a better term for its behavior - it only allows access to the disk controller when the RAM card is switched off - system errors out if trying to run the CFG file from E/A or Running the Load program from Extended Basic when it is in the on position. 
 

I hope this isn’t too confusing but I’m trying to resolve this cards condition and have been listening and attempting any recommendations that come my way!

 

Thank you all for all the help!

 

I appreciate it!

It still sounds like it is always enabled at all cru locations.

 

Can you try removing the dip switch block and both 259 chips, that should be similar as being in the off position and the led should be off then.

 

If not, then there something wrong elsewhere in the address decode logic.

 

Do you have like finalgrom99 or something similar where you can run a memory editor program, would be interesting see what is at the 4000 space and memory editor program you can also manually set cru bits to enable and disable cards.

 

Have you been able to run the TST program from 8.14f -- did you also try CFG from 8.14f

 

Have you try removing the 32k onboard and using a normal 32k card.

 

Have you try replacing the 8k dsr ram chip?

[NewcomerTI]

25 minutes ago, Gary from OPA said:

It still sounds like it is always enabled at all cru locations.

 

Can you try removing the dip switch block and both 259 chips, that should be similar as being in the off position and the led should be off then.

 

If not, then there something wrong elsewhere in the address decode logic.

 

Do you have like finalgrom99 or something similar where you can run a memory editor program, would be interesting see what is at the 4000 space and memory editor program you can also manually set cru bits to enable and disable cards.

 

Have you been able to run the TST program from 8.14f -- did you also try CFG from 8.14f

 

Have you try removing the 32k onboard and using a normal 32k card.

 

Have you try replacing the 8k dsr ram chip?

I tried just removing the dip switch block and the LED went out. Didn’t have to remove the 259’s as it went out (essentially just turning off the block does the same thing and the LED goes out) 

 

I do not have a Finalgrom99 but I have a mini memory cartridge.  Would that set the memory space of 4000 to what I would want?  I’m unsure about the process but any suggestions I’ll follow up on it. 
 

TST did run and I have no errors on the memory and on U11 no errors. 
 

i removed the on board 32K chip and ran with the 32K normal card - no change. 
 

im unsure what the 8K DSR RAM chip is.

 

when I peek at the 4000 space I get this:

easy bug menu item ‘C’ followed by the ‘4000’ and a few space bars - is this tell us anything?

[NewcomerTI]

You asked “did you also try CFG from 8.14f” ?  

I have tried to figure what version I have running when I look it doesn’t say or I’m not looking in the correct spot for the version. I think it is saying version 8.42c if that makes sense…

I sometimes can trick the system to recognize when the switch is in the 1000 position to get it to recognize the RAM card but not the disk controller or RS232 PIO card. I have to be good at turning the switch (on the RAM card) on at the right time to capture that moment.  

[NewcomerTI]

Tonight I removed CR4 out of the circuit and I was delighted to see all the extraneous ‘phantom’ cards disappeared. It actually recognizes the disk controller and RS232 and PIO together with the RAM card.  However the front LED is still on solid. So unfortunately it will not load the ROS.

 

i need help in deciphering what taking out that germanium diode causes in the circuit or more clearly what steps to take to remedy or troubleshoot further to get this card to configure. Any ideas that I could attempt?
 

The system gets to the point where it doesn’t progress or ‘hangs’ without giving the next menu (to Quit, Next, Load, Save, Font, Edit, Dsk, User screen) without that diode in the circuit.  Incidentally, I did change out CR4 with a spare that I had with no change in the fact that I have a solid LED on the front side and I am unable to get the card to configure. 

[Gary from OPA]

i would replace all the diodes, they are major part that causes alot of issues if one of the 4 are bad, as they act as decode gate for the logic and memory access.

[NewcomerTI]

Thanks for the reply I’ll see what I have in stock here, can’t a test be done on them to check their bias and reverse?  After I resoldered the diode back in it gave the old screen with all the cards showing up as unknown. 

[Gary from OPA]

49 minutes ago, NewcomerTI said:

Thanks for the reply I’ll see what I have in stock here, can’t a test be done on them to check their bias and reverse?  After I resoldered the diode back in it gave the old screen with all the cards showing up as unknown. 

I always found it iffy to test the diodes, best to just scrap them all and replace them good new ones. Even old stock might be iffy. I would order a set of new compatible ones from a reliable place. Personally, I always hated the fact the Horizon design uses diodes, there has to be a more realistic way to do it, but one reason back then and I think still is because of the battery backup.

[RickyDean]

6 hours ago, NewcomerTI said:

Thanks for the reply I’ll see what I have in stock here, can’t a test be done on them to check their bias and reverse?  After I resoldered the diode back in it gave the old screen with all the cards showing up as unknown. 

Are you using the Russian D7K's or the IN34A's. If you are using the Russian diodes, the black band goes on the opposite side from the installation of the IN34A's.

[NewcomerTI]

10 hours ago, RickyDean said:

Are you using the Russian D7K's or the IN34A's. If you are using the Russian diodes, the black band goes on the opposite side from the installation of the IN34A's.

I attempted installing (new) 1N34A’s now.  I just run CFG1 and only the RAM card shows up with the other ‘phantom’ cards appearing. I can remove the CR 4 diode one more and that ‘appears’ to be more accurate of what is in the PEB - won’t get past the load portion of the ROS ‘hangs’ on the ‘Press any key’ item. 

[RickyDean]

On 6/19/2024 at 2:16 AM, NewcomerTI said:

im unsure what the 8K DSR RAM chip is.

 

The last Sram chip setting just above the 2 74LS244 and 1 74ls245 chip, and with the middle led light just to the left of it, is the DSR chip. It is a 28 pin  SRam chip that is loaded with the ROS and stays battery backed, keeping the ROS intact. Historically it holds an 8k sram chip, but I use 32k sram in mine. since you are having issues with loading a ros, could your DSR chip be bad? Do you have a  mini pro or another device to test it? Maybe try it in your working one.

Edited June 21 by RickyDean

[+InsaneMultitasker]

1 hour ago, NewcomerTI said:

I attempted installing (new) 1N34A’s now.  I just run CFG1 and only the RAM card shows up with the other ‘phantom’ cards appearing. I can remove the CR 4 diode one more and that ‘appears’ to be more accurate of what is in the PEB - won’t get past the load portion of the ROS ‘hangs’ on the ‘Press any key’ item. 

Until you resolve the phantom card issue, there is no sense in trying to load ROS.  You need to resolve the immediate issue first.

[NewcomerTI]

44 minutes ago, RickyDean said:

The last Sram chip setting just above the 2 74LS244 and 1 74ls245 chip, and with the middle led light just to the left of it, is the DSR chip. It is a 28 pin  SRam chip that is loaded with the ROS and stays battery backed, keeping the ROS intact. Historically it holds an 8k sram chip, but I use 32k sram in mine. since you are having issues with loading a ros, could your DSR chip be bad? Do you have a  mini pro or another device to test it? Maybe try it in your working one.

That 32k SRAM is interchangeable with the 32K expansion chip so I have replaced it with the three that I had on hand. I do not have a mini pro. 
 

Thanks,

 

Ray

[NewcomerTI]

38 minutes ago, InsaneMultitasker said:

Until you resolve the phantom card issue, there is no sense in trying to load ROS.  You need to resolve the immediate issue first.

Gotcha. Trying different angles to get to it. I am thinking if I could find the missing lead that that would resolve this card being finicky.

 

Thanks,

 

Ray

[+InsaneMultitasker]

8 minutes ago, NewcomerTI said:

Gotcha. Trying different angles to get to it. I am thinking if I could find the missing lead that that would resolve this card being finicky.

 

Thanks,

 

Ray

Yep, and hopefully the solution will show itself soon.

Have you confirmed that R13 and R12 are installed and connected as depicted? These components are sometimes overlooked but are also important to the CRU decode.

 

[NewcomerTI]

Yes I double checked the R12 and R13 locations and both resistors are there and the correct ohms. I’m not sure if this gives any clarity or not but I was fooling around with the 4ADSRLD & 4ADSRSV - and I got the card to recognize the DSR from the floppy controller. 

 

however even though the card says success on loading a ROS, it indicates on the very next screen that No Valid ROS is loaded…

 

is there a correct DSR that I need to load?   Thanks in advance for any information. 
 

Thanks,

Ray

[Gary from OPA]

1 hour ago, NewcomerTI said:

Yes I double checked the R12 and R13 locations and both resistors are there and the correct ohms. I’m not sure if this gives any clarity or not but I was fooling around with the 4ADSRLD & 4ADSRSV - and I got the card to recognize the DSR from the floppy controller. 

 

however even though the card says success on loading a ROS, it indicates on the very next screen that No Valid ROS is loaded…

 

is there a correct DSR that I need to load?   Thanks in advance for any information. 
 

Thanks,

Ray

There really only one DSR for the horizon, the latest v8.42c and the last one by me the v8.14f

 

But, until you get a proper screen like this showing your cards, it's not worth trying anything else.

[NewcomerTI]

I’m trying.  I had gone over this board trying to see where there might not be a connection made or where there may be an inadvertent solder ball or connection made where there should not be and I keep coming up empty handed. Still trying!

[+InsaneMultitasker]

23 hours ago, Gary from OPA said:

But, until you get a proper screen like this showing your cards, it's not worth trying anything else.

That's cool, seeing all of those cards in the same system    What is the device at >1400?