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Tandy 1000 Upgrade Wishlist

G

Great Hierophant

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1. Tandy 1000 Keyboard Converter
The original 1000 keyboard is not the worst keyboard, but if you do not have one or one of the keyboards that can be made to work with it, then your Tandy 1000/SX/TX is a large paperweight. A converter would allow XT and AT keyboards to work with the Tandy 1000s with an 8-pin DIN keyboard interface. Recently the official Tandy solution was revealed, but it has its limitations

2. Digital Joystick Adapter
Analog joysticks are not necessary for many PC games, which work just fine with a Gravis Gamepad or similar controller that can simulate an analog controller without the hassle of trimmers. Unfortunately, they do not work with Tandy 1000 joystick interface, so another kind of adapter is required. Recently one was proposed, but the original poster seems to have vanished.

3. DA-15 to 6-pin DIN Tandy Joystick Adapter
A professionally done adapter would allow easy plugging in of any PC gameport joystick to the Tandy ports with ease, but the joystick will still require a trivial modification.

4. Memory and DMA Upgrade Board for Tandy 1000
The Tandy 1000 only came with 128KB, the rest had to be added by an upgrade card. Additionally, it did not include DMA. The 1000 only came with three upgrade slots, and the original solution required two of them to obtain 640KB and DMA. A later undoubtedly more rare solution had the extra RAM, DMA functionality and even a PLUS-style riser to add a serial or modem card without taking up the second slot.

5. Memory and DMA Upgrade Board for Tandy for Tandy 1000EX/HX
This board adds DMA and provides the remainder of RAM needed to get to 640KB for the EX and HX, but uses the Tandy Plus card form factor. The EX and HX are really not working at their full potential without this device, which also allows you to add two more cards above it. You would think these were sold at nearly a 1:1 ratio with the machines, but you would be very much mistaken.

6. Serial Port Adapter for Tandy 1000EX/HX
Mouse support is useful for any PC, but unless you want to use a mouse via a gameport, you must look to this. The original card adds a serial port for the EX and HX, but a modern version should be able to add two ports with ease.

7. XT-IDE Adapter for Tandy 1000EX/HX
The XT-IDE adapters are small enough to fit in the PLUS form factor, so someone should make one, preferably with a CF slot, so that these machines can enjoy proper large hard drive support.

8. Parallel Port Ethernet Adapter for the Card Edge Parallel Port
The Tandy parallel port is missing a signal that is vital to the common Xircom PE3 parallel ethernet adapters. A new design may be required, preferably one which can handle the birdirectional function of the Tandy 1000 parallel ports This is especially important for computers like the 1000 RL, which has a DB-25 but the signal is still missing and it only has one expansion slot. Not required for the TL/3, RLX or RSX.

9. 8-bit XTA Adapter
For the TL/2, RL and RLX, these systems contain an 8-bit ATA interface supporting 20 and 40MB drives. Even though modern CF cards have an 8-bit mode, they have to be told to use it. The adapter would essentially initialize the CF card. Moreover, they may need to have their geometry translated to look like a 20 or 40MB drive. These machines suffer from a lack of slots, so this would be very useful for them.

10. V30 Upgrade for 1000RL
The RL uses a 44-pin PLCC-packaged 8086 which is surface mounted. The NEC V30 (μPD70116) is extremely difficult to find in that packaging. DIP V30s (40-pin) are much easier to find. This would involve fitting a PLCC socket to the board and then using a PLCC riser to a DIP socket adapter for a DIP V30. Because of the complexity, this would be more of a service than a product.
 
Great Hierophant said:
8. Parallel Port Ethernet Adapter for the Card Edge Parallel Port
The Tandy parallel port is missing a signal that is vital to the common Xircom PE3 parallel ethernet adapters. A new design may be required, preferably one which can handle the birdirectional function of the Tandy 1000 parallel ports This is especially important for computers like the 1000 RL, which has a DB-25 but the signal is still missing and it only has one expansion slot. Not required for the TL/3, RLX or RSX.
Click to expand...
Is that parallel port compatible/useable with LapLink and DOS' INTERSVR/INTERLNK and a parallel transfer cable? If so, there is software to run a complete Server/Workstation network via the parallel ports of two machines -- no (Ethernet) adapter required. It's kinda like Lantastic Z but 100 times simpler/easier. :)
 
As far as the memory upgrade is concerned, a simpler option, sans DMA using static RAM could be done too I'd think. Apart from using the DMA capability for the the FDC, the DMA's primary purpose in the factory RAM upgrade option was DRAM refresh and to populate the other DMA signals on the PLUS card connectors to the additional two cards. In practice though you're probably not likely to find a plus card with DMA capability.
 
Yeah, I'd love to get a decent solution for putting a V30 in my RL...one of these days when I have some experience with surface-mount stuff I might take a stab at it, but that won't be any time soon...
 
geoffm3 said:
As far as the memory upgrade is concerned, a simpler option, sans DMA using static RAM could be done too I'd think. Apart from using the DMA capability for the the FDC, the DMA's primary purpose in the factory RAM upgrade option was DRAM refresh and to populate the other DMA signals on the PLUS card connectors to the additional two cards. In practice though you're probably not likely to find a plus card with DMA capability.
Click to expand...

You would need only 512KB chip for the Tandy 1000 or a 256KB chip for the EX or HX. You would save quite a few chips that way, not just the memory but also the logic necessary to allow for proper addressing. You would also gain a tiny speed boost.

Tandy's PLUS Memory Expansion board added 256KB in eight RAM chips and used an ASIC chip to provide for the DMA function. See it on this page : http://www.oldskool.org/guides/tvdog/HXEX.html
It can be done, but I would suggest using the real 8237 with the space you save by using SRAM chips and a smaller CLPD or FPGA to handle all the glue logic.

I wonder if the machines will spit an error at you if it detects the memory but not the DMA. In the original design, the first memory expansion card had the DMA chip and the second one was identical except it had an empty socket.

Stone said:
Is that parallel port compatible/useable with LapLink and DOS' INTERSVR/INTERLNK and a parallel transfer cable? If so, there is software to run a complete Server/Workstation network via the parallel ports of two machines -- no (Ethernet) adapter required. It's kinda like Lantastic Z but 100 times simpler/easier. :)
Click to expand...

It is useable with LapLink and DOS' INTERSVR/INTERLNK, although I do not believe that Microsoft's software supports bidirectional mode.
 
Stone said:
Is that parallel port compatible/useable with LapLink and DOS' INTERSVR/INTERLNK and a parallel transfer cable? If so, there is software to run a complete Server/Workstation network via the parallel ports of two machines -- no (Ethernet) adapter required. It's kinda like Lantastic Z but 100 times simpler/easier. :)
Click to expand...

Yes. Laplink even offered the special cable that was needed for $15. Of course, that also requires a time machine to go back to 1988 so most will find it easier to get instructions on building an adapter from the OP's website.

I believe Tandy offered a Xircom Pocket parallel port adapter for the Tandy 1000 which presumably had whatever fixes were needed to deal with the unusual card edge port style. Admittedly, by the time Tandy introduced it and at Tandy's pricing, buying a new computer looked like a much better value.
 
krebizfan said:
Yes. Laplink even offered the special cable that was needed for $15. Of course, that also requires a time machine to go back to 1988 so most will find it easier to get instructions on building an adapter from the OP's website.
Click to expand...
The cable isn't so special. Every computer store used to have it in stock generically. It's called a parallel transfer cable. Here's the diagram...

Use data grade cable, 11 wires with shield and male DB-25 connectors. Wiring is as follows:

Code: 
Pin      2      to      Pin     15
 -       3      --      ---     13
 -       4      --      ---     12
 -       5      --      ---     10
 -       6      --      ---     11
 -      10      --      ---      5
 -      11      --      ---      6
 -      12      --      ---      4
 -      13      --      ---      3
 -      15      --      ---      2
 -      25      --      ---     25 
(Also connect both pins 25 to shield)
 
Great Hierophant said:
You would need only 512KB chip for the Tandy 1000 or a 256KB chip for the EX or HX. You would save quite a few chips that way, not just the memory but also the logic necessary to allow for proper addressing. You would also gain a tiny speed boost.

Tandy's PLUS Memory Expansion board added 256KB in eight RAM chips and used an ASIC chip to provide for the DMA function. See it on this page : http://www.oldskool.org/guides/tvdog/HXEX.html
It can be done, but I would suggest using the real 8237 with the space you save by using SRAM chips and a smaller CLPD or FPGA to handle all the glue logic.
Click to expand...

Yep...

Back when I still had an HX, I tinkered with the PLUS memory card in it to see if I could bump it up to a total of 768kB, just to see if you could move the video RAM past the first 640kB like you can the TX. The same ASIC is used for the EX/HX for expansion memory is also used in the TX on the motherboard, they apparently just jumper it differently. I removed the rows of 4164s and piggybacked another row of 41256s on top of the existing row of 41256s on the card, changed the jumper settings to match the datasheet info in the TX tech manual and connected the RAS/CAS signals to the additional RAM from one of the 64kb banks on the card and no dice, completely dead system. Seems like it should have worked. I wonder if the BIOS does some detection on the ASIC to figure out what mode it's in and got confused? Never investigated it further.
 
I am always confused about the specials a my RL has. The lack of a real parallel-port is really a big thing. I do not want to make connections on the board, even then a zipdrive is not usable.
I think I should go for the laplink in order to transfer data from and to the xtide in my RL. Because my floppy was defective I always opened the case an pulled out the CF-Cards in order to
get software on it. Perhaps that Laplink is a good option for me. I think I will go for such a cable if I do not have to change something on the board.
 
I like the CGA of the Tandy but in comparison to the hercules of my euro-pc and the ega on my tower at, the cga is much worse displaying text an gfx,
because of the smaller resolution (200lines). Therefore a EGA or VGA Adapter with a fallback to TGA in games would be a nice thing. such things already
extist with a software (afaik VGA->TGA and back, but there was an issue with EGA->TGA and back). In order to get the 8Bit-Slot free from my xtide it
would be nice to get a connection between the 8bit IDE interface an s CF-Card, but I think this would not be happen anytime.
 
I like Ethernet because it allows for long cables and file transfer with even the most modern system is very easy. Set your Tandy (or any DOS-running PC) to act as a FTP Server, which can be done easily using Mike Brutman's FTPSRV from his mTCP suite package. Then use an FTP Client on the modern system and manipulate the older system's drives at will.

The older Tandys (EX, HX, SX and TX) contained their parallel port logic within a single parallel port array chip. When I viewed the pinouts for this chip, I observed that the missing signal (Control Port Select, NOT Status Port Select), was available at an unconnected pin. It would only involve a wire and a resistor and a capacitor to connect it to an unused pin on the card edge. Unfortunately, the later Tandys (all TLs, SLs and RLs except TL/3), do not bring this signal to a pin, so those owners are out of luck. The RL's get an especially short shrift because they do not need an adapter but only have one slot.

Strangely, all Tandys only need a jumper or a bit of solder to connect the Status Port Select to the card edge (or DB-25 for the RL). This allows Laplink to work in 5-bit I/O mode, but that is not nearly as fast as 8-bit I/O.
 
Thank you for making that clear.

RL:
- Laplink without modifikation of the board -> NO!
- Laplink with added connection on the board -> slow but working
- Zipdrive -> no way even with the modification above.

pretty stupid!
 
I've had interest in building a Plus riser in the past to use instead of the DMA+memory riser. The main problem is finding a turn-key source for the stacking .1" 61 pin IDC headers. You can't stack PLUS boards on top of one another natively. You can only mount 1 PLUS board directly to the MB. If that board is the Mem+DMA, it provides two more headers above for another two cards.
 
eeguru said:
I've had interest in building a Plus riser in the past to use instead of the DMA+memory riser. The main problem is finding a turn-key source for the stacking .1" 61 pin IDC headers. You can't stack PLUS boards on top of one another natively. You can only mount 1 PLUS board directly to the MB. If that board is the Mem+DMA, it provides two more headers above for another two cards.
Click to expand...

Actually I took another look at the DMA board. It seems they used Molex standard IDC headers that have very long pins like a 42375 series. That series has gold plating on the last .4" of the pin just like the Tandy pins. Then it seems they they press fit or heat fit a separate shroud on-to the top of the pins. They also used a break-away variety as I can clearly see breaks on one side of the pin array and molded finish on the other. So the connector turns out to be non-standard after all even in the original Tandy boards.

The longest pins in the Molex 42375 series have a mating length of 1" - about .2" shorter than the Tandy card. So I'm still stuck on options.

One alternative possibility is to build an after-market two card set. One that adds functionality 'a' and includes a cascading connector on top for one card only. Then add another card that adds functionality 'b' and again a cascading connector for a third standard PLUS card. Functionality 'a' could include memory, DMA, and a serial port. Functionality 'b' could include IDE or SD-card, storage ROM BIOS, and a second serial port. Then add whatever PLUS card you need on top. The downside is you would not be able to add two original PLUS cards to a system.

Another possibility is the stacking height for PLUS cards exactly matches PC104. I've already layed out a PC104 PLUS adapter sometime back. Would not include a back plate, but you could add two 104 cards to an EX/HX.
 
dr.zeissler said:
RL:
- Zipdrive -> no way even with the modification above.
Click to expand...

For added clarification (again), a SCSI Zip drive can be used on the RL's parallel port, through the intermediary use of Shuttle-based parallel-to-SCSI adapter, and when the Select (status) line on the RL's motherboard has been connected by jumper or otherwise. As mentioned elsewhere, I've also successfully used this same setup on a TL/2, but requiring the additional use of a homemade DB25 adapter, given the card-edge parallel port.

 
Hi everyone. I recently started a thread about possibly creating a small modern 8-bit ISA card with a plus card adapter that would work on the 1000 line and add a few features. It seams that thread is waiting on an admin but this seems related.

I thought a lot of Tandy fans have a want to have maximum memory and a HDD interface. Since it is hard to get a CGA monitor (VGA output) and CPU upgrades are common those features would be a big plus. While networking 10T and modern interfaces (USB,SD,Serial,Parallel and game port) are always on a list.

If I can get a team together to design a board similar to the Amiga Dragon II with an FPGA we could get all the most common upgrade needs and maybe some rare ones integrated to a very small card that works in all 8-bit Tandy and maybe some IBM/Clones too. I'm sure they would sell a modest amount and make collecting and restoring much more affordable and fun.

Any interest in that sort of modern upgrade?
 
Great Hierophant said:
It would only involve a wire and a resistor and a capacitor to connect it to an unused pin on the card edge. Unfortunately, the later Tandys (all TLs, SLs and RLs except TL/3), do not bring this signal to a pin, so those owners are out of luck. The RL's get an especially short shrift because they do not need an adapter but only have one slot.
Click to expand...

Just a heads up I have a TL/3 and can confirm that the Xircom is not detected/working via the built-in parallel port. I looked at the the 1K Tech Notes & Jumper reference but it didn't list any printer select jumper for it. Works fine via a ISA parallel card set to LPT2. I'll also test it on the RLX when I can.
 
TandySYC said:
Hi everyone. I recently started a thread about possibly creating a small modern 8-bit ISA card with a plus card adapter that would work on the 1000 line and add a few features. It seams that thread is waiting on an admin but this seems related.

I thought a lot of Tandy fans have a want to have maximum memory and a HDD interface. Since it is hard to get a CGA monitor (VGA output) and CPU upgrades are common those features would be a big plus. While networking 10T and modern interfaces (USB,SD,Serial,Parallel and game port) are always on a list.

If I can get a team together to design a board similar to the Amiga Dragon II with an FPGA we could get all the most common upgrade needs and maybe some rare ones integrated to a very small card that works in all 8-bit Tandy and maybe some IBM/Clones too. I'm sure they would sell a modest amount and make collecting and restoring much more affordable and fun.

Any interest in that sort of modern upgrade?
Click to expand...

The ISA-PLUS adapter is easy, I already make those.

The rest is a lot harder but a damn good idea nonetheless - Im only fairly new at digital circuit design + I cant program to save my life so I wouldn't be able to contribute.
 
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