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InsaneMultitasker

Myarc cards for sale/repair tips

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3 hours ago, InsaneMultitasker said:

This evening my Geneve glitched again so I put the card into the PEB extender. I couldn't make the ram fail again with any tap-tests, however, my infrared temp gun registered 182F (83C) on the lowest stack of VRAM

 

It looks like the ambient temperature max is 70C but I can't seem to find the reference to max operating temp.   

 

Anyone know of a good source to buy (or have some to sell) good, working video memory chips ?

 

If I feel up to it, I will replace the sockets and replace the power regulators with dc-to-dc converters to match Heatwave's configuration.  I've resisted modifying my workhouse Geneve but it might be time to put it on the bench.

jameco has 41464's in stock

 

41464-10: Major Brands : IC 41464-10 DRAM 256K-Bit (64Kx4) 100ns w/Page Mode (HY53C464S-10) : ICs & Semiconductors (jameco.com)

 

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Well, I decided to use a dual wipe socket for the upper level of the flash eeproms, there is the board level socket, or in my case sipps, then the next socket is the one that receives the wires. I got them soldered on and the eeproms in place, just have to solder a wire to the upper eeprom for completion. The next thing to do is decide whether to go with another 128k stack, or a single 512k sram chip. Have both, so just have to look at what I need to do. Sorry about the shadow, took this outside in the sunlight.

20210311_115519.jpg

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4 minutes ago, dhe said:

RickyDean, you have persevered, fair longer then most people!

Thank you, keep in mind that right now I'm on unemployment and working on umpteen projects around the house and in the house. In the last few days I've repaired a generator, finished a total rebuild on a Samsung front load washer, and am continuing work on placing  GM LS engine and transmission and transfercase into a 89 Grand Wagoneer. I have been rebuilding my  wds-100 personality card, almost ready, and still diagnosing corcomp disk controller issues on my two corcomp cards, and have assembled a Rubbermaid 7x3 shed. So I am, one hard headed and determined fellow. A long way to go and a shorter time to get there.

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11 minutes ago, RickyDean said:

Oh, Insane one, my Geneve doesn't have this resistor. What is it's significance?

E76BF554edited.jpg

That resistor is installed to make it more difficult to remove the 9995.

 

I'll check my notes tomorrow.  It's probably there to pull one of the two inputs low to ensure the proper PFM bank is active on start-up.  Check your board for a resistor 'under' the 9901.  This mod seems to have almost as many flavors as Baskin Robbins.

 

 

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11 hours ago, RickyDean said:

20210311_115519.jpg

I could probably run these lines more haphazardly for you...

522171999_WEspool.thumb.JPG.541fad36d4fb45e7497d34206706d7db.JPG

This was 2500' ...when I started.

Hmm, where did its sister roll go?:ponder:

 

 P.S. This is premium, standard Western Electric telephone wire.:grin:

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57 minutes ago, InsaneMultitasker said:

That resistor is installed to make it more difficult to remove the 9995.

 

I'll check my notes tomorrow.  It's probably there to pull one of the two inputs low to ensure the proper PFM bank is active on start-up.  Check your board for a resistor 'under' the 9901.  This mod seems to have almost as many flavors as Baskin Robbins.

 

 

No resistor under the 9901!

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30 minutes ago, HOME AUTOMATION said:

I could probably run these lines more haphazardly for you...

522171999_WEspool.thumb.JPG.541fad36d4fb45e7497d34206706d7db.JPG

This was 2500' ...when I started.

Hmm, where did its sister roll go?:ponder:

 

 P.S. This is premium, standard Western Electric telephone wire.:grin:

You probably could, these are pretty much as they cam to me from Cecure those decades ago. Plus, there are several disconnected from their places....😆

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1 hour ago, RickyDean said:

No resistor under the 9901!

Let me re-phrase:  are there any resistors connected to the 9901 on the underside of the board?    There should be at minimum one resistor connected to the 9901, pin 20.  Based on CRU addresses for the device, the second resistor should be tied into the 139 - where the wire leads to the 9901 or on the chip itself.   I'll confirm tomorrow.

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6 hours ago, InsaneMultitasker said:

Let me re-phrase:  are there any resistors connected to the 9901 on the underside of the board?    There should be at minimum one resistor connected to the 9901, pin 20.  Based on CRU addresses for the device, the second resistor should be tied into the 139 - where the wire leads to the 9901 or on the chip itself.   I'll confirm tomorrow.

Yes, it was late, should have thought of that, my 62 year old brain wasn't clicking.

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On 3/12/2021 at 6:42 AM, RickyDean said:

Yes, it was late, should have thought of that,

Confirmed - there should be one resistor attached to the 9901 pin 20 and another to the 9901 pin 32, provided I counted pins correctly. The installation of the resistor was moved to the underside of the board. 

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I flipped through my old notebooks and found a sketched "schematic" of the PFMPLUS/PFM+ from the 90s.  I cannot attest to its accuracy though most of it "looks and feels" correct.  In some of my other drawings, jumpers and pins were intentionally mirrored or flipped to obfuscate the modification.  The suspicious exceptions to confirm include the resistor values and the JM1/JM3 orientation. 

 

Seems at this time we were at least documenting wire colors to some pins.  The 9901 pin 32 resistor is still mounted to the LS139 (versus to the underside of the 9901) in this markup. 

 

707730335_PFMPLUSpartialschematic1990s.thumb.jpeg.02c62ed868f05eef02ef84c0f7cdcb7b.jpeg

(Edit: I'm also not clear on what the penciled-in pins in the upper right corner represent)

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3 hours ago, InsaneMultitasker said:

I flipped through my old notebooks and found a sketched "schematic" of the PFMPLUS/PFM+ from the 90s.  I cannot attest to its accuracy though most of it "looks and feels" correct.  In some of my other drawings, jumpers and pins were intentionally mirrored or flipped to obfuscate the modification.  The suspicious exceptions to confirm include the resistor values and the JM1/JM3 orientation. 

 

Seems at this time we were at least documenting wire colors to some pins.  The 9901 pin 32 resistor is still mounted to the LS139 (versus to the underside of the 9901) in this markup. 

 

707730335_PFMPLUSpartialschematic1990s.thumb.jpeg.02c62ed868f05eef02ef84c0f7cdcb7b.jpeg

(Edit: I'm also not clear on what the penciled-in pins in the upper right corner represent)

Thanks, I'm sure that these will help, I'll get back on it sometime this week, I was making my own notes too.

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I replaced the VRAM in my development Geneve and I am happy to report that there were no glitches over the weekend. 

 

When I removed the 192K VRAM stack one of the wires looked loose -- the wire had broken but the plastic coating was still connected to the chip lead.  Did the wire break before or after I removed the stack?  I don't know. 

 

For now I'm just running 128K which is fine in most cases, unless I want to use YAPP or some other program requiring 192K VRAM.

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I am going to Knoxville this weekend to celebrate some birthdays this month, so it will probably be next week before I delve back into the PFM Geneve repair.  I have been and will be busy this week to include getting ready for the trip. Grand daughter wants "papaw" to see her turn 6!!

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Last night I updated my PFM512 Geneve's core and OS and earlier today, I crossed my fingers and pulled the trigger, applying the same updates to my PFM+ Geneve.   The system cores are now at the same revision and can hold the full 136K Geneve OS. The product ID and CRC tests have been removed, so one core will function with the Atmel 29c010, 29040, 29c040a, and WinBond W29c040.

 

As with version 7 of the core, the built-in OS and flashdisk programming are no longer viable.  Command line tools take the place of the built-in routines.  I'm still working out a few protection measures (e.g., not allowing the 512k flashdisk loader to execute with a PFM+,  simple CRU/wire-fault detection) before I release the programs.  

 

Picture of the PFM+ (two 29c010 chips) running the pfm512 version of the core.

 

image.png.882a0f5fd00f6cc2a2c700913694d095.png

 

Update: So far everything seems stable with my system, however, @9640News  's  PFM+ isn't responding to the product identification routine.  

It is a bit baffling though at the moment we suspect a timing issue.  More testing tomorrow.  We don't want to initiate a core update before this is figured out. 

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Well, I think I've settled on a strategy for adding the 512K chip to my pfm+. I am going to install a board between the chip and socket and the underside of the board place a 74 LS138 unmodified into a socket added to that board with the correct wires routed per Fabrice's mod, similar to Shift838's smd board. Then I'm going to do the same under the two flash eeproms, with the 74ls139. Then the sound chip can go back unmolested, after I divest it of its burden, back into its own socket. This is the plan, we'll see.

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On 3/27/2021 at 4:59 PM, InsaneMultitasker said:

 

Update: So far everything seems stable with my system, however, @9640News  's  PFM+ isn't responding to the product identification routine.  

It is a bit baffling though at the moment we suspect a timing issue.  More testing tomorrow.  We don't want to initiate a core update before this is figured out.

I found a spare PFM+ stack and installed it (replaced the existing chip stack) into my working Geneve.  Everything worked fine except for the PFM identification.  As best I can tell, the LS139 is interfering with the ID sequence when the flashdisk chip is selected.  This makes little sense except that the LS139 Select line may be flip-flopping the chips during the operation.  The fix for my Geneve was to force the 9901 to select the system chip prior to the ID sequence.

 

I've attached the identification program.  I would appreciate it if a few of you with the PFM512 or PFM+ could run it then share the resulting text, along with the type of PFM in your Geneve. 

 

PFMPROD  (tifiles format)

 

Edit: I updated the core standalone utilities and proceeded to upgrade the spare PFM stack from v3.0 to v8.0 then updated the installed MDOS from 2.21 to 7.22 - so far all is working as expected.

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I have wait till I get the diodes, called out in Fabrice's 384k mod, will run this on mine when I get it finished, but may be a week or two. Do have the rest of the BOM and my home built pcb's for continued work though.

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5 hours ago, InsaneMultitasker said:

I found a spare PFM+ stack and installed it (replaced the existing chip stack) into my working Geneve.  Everything worked fine except for the PFM identification.  As best I can tell, the LS139 is interfering with the ID sequence when the flashdisk chip is selected.  This makes little sense except that the LS139 Select line may be flip-flopping the chips during the operation.  The fix for my Geneve was to force the 9901 to select the system chip prior to the ID sequence.

 

I've attached the identification program.  I would appreciate it if a few of you with the PFM512 or PFM+ could run it then share the resulting text, along with the type of PFM in your Geneve. 

 

PFMPROD  (tifiles format)

 

Edit: I updated the core standalone utilities and proceeded to upgrade the spare PFM stack from v3.0 to v8.0 then updated the installed MDOS from 2.21 to 7.22 - so far all is working as expected.

 

 

Hi, so here is the info from my PFM one:

(How much Standard/(PFM)/(Extra)-(S)RAM do I have?) :)

 

Geneve-PFM-RMS-13--PFMPROD-MEMMAP.thumb.JPG.287617cebb24fb3e6a1887f71eab0bc3.JPG

 

 

 

Geneve-PFM-RMS-12--MEMEDITOR1.thumb.JPG.11e31dd42330e010eee8db422191b1e1.JPG

 

 

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5 hours ago, Schmitzi said:

Hi, so here is the info from my PFM one:

(How much Standard/(PFM)/(Extra)-(S)RAM do I have?)

You have the standard Geneve memory + 384K memory upgrade.   The PFM device is separate from the 384K RAM and is programmable flash EEPROMs.  The PFM+ is two x 128K Atmel 29c010 chips, as identified :)   Hooray, it worked!   Your PFM+ is a candidate for updating and loading MDOS 7.xx when released. 

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And I will be testing my system tonight, and hopefully making the commit to update to the CORE V7 version.

 

 

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