Swim

My favorite solution for the IDE has always been the bq4852YMC-85 like the one listed here. The TI has gone obsolete but the Rochester one is still available. https://www.digikey.com/product-detail/en/rochester-electronics-llc/BQ4852YMC-85/2156-BQ4852YMC-85-TI-ND/11538020

Looking forward to getting an assembled version for my SNUG sys. The monitor I have on it now has started rolling when it's cold.

Will this be a parts kit or prebuilt unit? Just curious was it the capacitors that went bad on the monitor?

If it's just the 4464's you think are bad you might be able to test the two socketted chips in your programmer and see if they are good. If they test good and you have to desolder the other 4464's don't forget to heatsink the chip temporarily while desoldering. Then once you have the chip out you can install sockets to make things easier in the future if problems return.

I agree, I also understand the limits of today's SNUG. They got overwhelmed by the USA market for the SGCPU series. They were not that many people to begin with and certainly not in existence as a business. I seem to recall one SNUG member getting over a hundred e-mails in one day. Some wound up burned out and I'm not sure how many members make up the club today or if the club still meets. I wish SNUG ASCSI2 DSR code weren't proprietary and could be made available to trusted TIer's. I have an ASCSI2 sitting here that I got for repair and about 3 WHT "G," which is also proprietary, with fried programmable logic needing repair. At one point I was told I would get some PLD's in a shipment of the EVPC2 cards when they came out but that shipment never came to pass. I still have some Lattice IspLSI 2064A chips I ordered for the "G" cards at the time. My last contact with SNUG was when I sold the remaining SNUG SPVMC stock I had in the USA here on AA.

There was a working relationship between WHT and SNUG that resulted in the 1.6 upgrade for the WHT series and the ASCSI2. I'm not familiar with developments post the 1.6 upgrade and Gazoo's SCSI boot and MDOS tweek for PDMA.

Have you checked the SNUG site? If it's not listed there send Harald Glaab an e-mail as he might be able to point you in the right direction.

FWIW a solid state storage solution the SCSI2SD device has proven successful. I have recently acquired this version 6.0 device for my SNUG system and so far it's working no problem but as with all things TI/Geneve your mileage may vary. Can be powered 5v or USB. I added the 25 pin SCSI 1 to 50 pin adapter.

If your "G" has the 1.6 upgrade that looks like the card in the pic above and you are able to boot from the SCSI BOOT EPROM intermittently I agree that the storage setup/device you are using is the next place to look. I've never tried your setup myself as we mostly just used SCSI 1 internal hard drives, SyQuest EZ-135 and ZIP drives with the cards during that 1998 - 2004 period. Also SCSI 1 internal CD ROM players were used when Wolfgang's CD Commander software came on the scene.

BTW jedimatt, it comes to mind one of the hardware upgrades that was part of the 1.6 upgrade was a Schottky diode at location D1 for those using ZIP drives so keep that in mind if you are booting from a ZIP drive.

The old grey matter isn't what it used to be and it's been years since I sent all the SCSI stuff back to Don when he sold the WHT SCSI rights to competition computer but going by what I've read above my gut tells me PDMA (Pseudo Direct Memory Access) is not turned on in MDOS. I'm assuming this "G" model has the 1.6 upgrade with a daughter board that changes the on board narrow package 32k to the wide package 32k? We had to make that change because the narrow package speed caused problems that the slower wide package solved. I'm forgetting versions of MDOS but it used to be that you had to turn PDMA on until Gazoo came up with his SCSI Boot EPROM and an MDOS change that had PDMA always on. I'll try to pull out my notes later today and go over Gazoo's notes on setting up the Geneve for SCSI Boot. I don't seem to recall any notes about GenMod requiring different parameters and basically the 1.6 WHT upgrade didn't care what Geneve you had as long as it had the 32k fast RAM upgrade. BTW, after the 1.6 upgrade the "G" model WHT SCSI controller is the thoroughbred of the series with the "F" being the most stable with all manufacturer drive combinations in my opinion, and the "E" being the slowest.

Hmmm? I have to start at the top of the page to see what's going on here. lol

Okay atrax, I still have lots of testing to do with this 4.0Mhz SNUG P system but as of today your TI-RS232 2.5Mhz/6.0Mhz EPROM is working with TELCO and OMEGA Terminal programs and next I will test with Fast Term and other programs. This mod makes for very noticeable speed increase with the ASCSI disk/file manipulation as well as normal Floppy 5.25/3.5 access. Time will tell if I've broken my SNUG system or improved it but it's easy enough to return the 3.0Mhz parts to fix it if I broke it.

I'm in.

The RS232 Rom is the one you sent. But I only made the one log-in with TELCO so I wouldn't really call it a test at this point. Time will tell.

First impressions and review of my TI-99\4a version 40 Stuck home from work due to health issues so I got bored and picked this project out of the pile on the work bench. I have been experimenting over the years with speeding up the stock 4a console. The result of those experiments created the console that has been reliably running the Hidden Reef BBS for the past few decades. That particular console has the 32k on the 16 bit buss and runs overclocked to 3.58Mhz. Back when I was playing around I think I tested out at least three versions of available designs that put the 32k on the 16 bit buss until finally settling on the design from System Ninety Nine User Group of Germany. The SNUG design required a daughter board which was produced by the group but was the most reliable of the designs I tried and added a couple of features handy for programmers and could be setup to toggle on and off so the console could still be used at stock speed for gamers. Back at that time I had also experimented with running at 4.0Mhz but found that 4.0 broke too much software and wouldn't boot with certain 3rd party hardware in the P-Box. All that said, I had chose a 4a motherboard with the NEC -3 VDP memory which is 150 nano second instead of some of the other 4a MB's with 200 nano second or slower VDP memory as the base for this project. If you are lucky you might find a 4a MB with NEC -5 VDP chips which are 100 nano seconds. First thing I did was remover the stock clock crystal and install a new 4.0Mhz clock crystal. Sure enough, it did boot but was very flaky and showed dropped characters and wrong colors as has happened in the past when I tried a 4.0Mhz crystal in a stock MB. I next removed the stock TMS9901 and installed a TMS9901-40 and also began replacing the 74LSXXX logic in the memory management circuit with 74HCTXXX logic and replaced the stock electrolytic capacitors with new capacitors. At this point, I rigged up the MB and booted it to make sure of my work to this point. It booted nicely and was helped by the TMS9901-40 being installed. Did some things like run the size command while in X-Basic, access DSK1 just to see what would work and what wouldn't. I then removed the TMS9900 from the MB and installed a TMS9900-40. Booted up the MB to check my work and it did boot and ran as expected. In the photos you can see I installed a RAM disk in the P-Box and formatted it and loaded software to it. I also made a log-in on the Hidden Reef using TELCO at 4800 baud and to my surprise the screen didn't show any dropped characters and I didn't experience any other problems I was expecting from past experience. It was late and I had lost energy so I left the system running the EKMEL Fish Tank software and went to bed. Now 14 hours later the system is still running nicely without having crashed. Tonight I hope to finish changing the remaining 74LSXXX logic with 74HCTXXX logic and also perform the SNUG 32k on the 16 bit buss mod to bring this MB up to running at 16 bit speed at 4.0Mhz. If I'm successful I will install this MB into the Hidden Reef system and make it the first S&T BBS running at 16 bit, 4.0Mhz speed.

So you are running the newest 8.33 update on your TL866CS?

It appears I have the labeled LEDs and the six vents. My software is currently 6.60. What version of the software actually removes the 21volts? The latest version I see on the site today for "old hardware" is 6.85 and the TL866II is 8.33?

Competition Computer was selling an EPROM for Super Sketch that added the option for printing. (BTW, what ever happened to Competition Computer? Anyone know?)

You're on a nice repair roll of late. Don't stop, keep going until the bench is clear.

Hello Friends, please note all available SNUG SPVMC cards have now been purchased and I have no more of the SNUG system cards remaining in my possession.

For those that have been reading this thread and are interested in obtaining the last SNUG SPVMC card I have in stock you can PM me for info and purchase arrangements. First come first served basis.

Good question, Jim.

Yes, will work in P-Box with stock TI or SNUG system. Works in Geneve system with slight mod to fully decode the signals. PM sent.

I'll check how many SPVMC cards I have left unsold and post here later. If Harald can accept payment for the card then I will ship one. Buyer will owe me insured shipping cost. FYI, SPVMC require a slight modification for use with the Geneve.