So one thing I missed in my comparison: the 3-in-1 solutions do not have a DMA controller. For most cases this is not a big deal since the 3-in-1 card has SRAM, so not needed for refresh (video chip refreshes the motherboard RAM). Some use cases do use DMA (i.e. specialized disk writing software, sound cards). If planning one of these use cases, you'd want to go with the "stack of cards!"
So, at present, I'm now aware of anyone building these cards, but the GitHub repos listed above in the description do include a bill of materials! Also, in addition to the 3 in 1 cards, there is also a 4 in 1, which includes a SmartWatch chip, but I don't believe includes a parallel port or second serial port. I've added a link above to the 4 in 1 repo.
A 3-in-1 v3 with with an ISA adapter for the upper slot would be perfect. COM1+LPT2 can fit on slot 1, COM2+CF can fit on 2, leaving 3 free for experimenting (ethernet / sound card / hercules video for 2nd display )
Unfortunately, it would be super limited both in physical space, and in available resources. With the V2 design, there are no available IRQs left on the expansion bus, and most of the upper address space is taken up with Upper Memory Blocks.
@@georgemaragos2378 I think we might be out of IRQs! But I have gotten Ethernet on these using a Xircom Pocket Ethernet III connected to a Google WiFi access point :)
They are great to have! If you are handy at building a card, you can grab the bill of materials, link in the description. Otherwise, you might check out the TRS-80/Tandy 1000 Facebook group to see if anyone is planning to run a batch of cards (link also in the description)
@@pitfalljerry you might be able to program the chip with a bootable floppy and XTCF software! If not, a ti866 plus will do the trick for flashing a chip!
Hi Chris! New subscriber! I didnt know there was a 3 in 1 v2 ! I keep having to swap between my mouse and wifi to serial modem. Having two com ports would be great!
Hey Chad! Welcome to the channel. Yea, this card is GREAT. I can't recall if you are in the TRS-80/Tandy 1000 Facebook group... occasionally someone will do a run of cards... but if not, I presume you could build one too! A "perfect" card would have networking built in too, but my Xircom PE3 seems to help there. Anyway, glad you are here and looking forward to chatting more!
Thanks for the great video! Quick question - I know the Tandy Memory Expansion card also included a DMA controller. Is this a feature of the "bundle of cards" solution over the 3-in-1? I don't believe the 3-in-1 includes a DMA controller right?
You are correct! Here's the designer's take on why there is no DMA controller on the 3 in 1: "Memory refresh on the 1000, A, HD, EX, and HX is handled by the video chip. The video chip can only access the RAM on the motherboard itself, and not on any expansion cards. Tandy used the DMA controller to handle DRAM refresh for the expansion card(s). Since this design uses SRAM, it does not need to be refreshed, so does not need a DMA controller."
Also from the designer: "There are a couple of edge cases that depend on Direct Memory Access as well, such as some disk image writing software, but they are few and far between. Same with some hardware, such as a Sound Blaster, which 1) wouldn’t natively fit, and 2) would take away from the Tandy 3 voice sound that the system is known for."
@@RetroTechChris Thanks! I recently got a Tandy 1000 EX, and it actually came with a Memory Expansion card already (extra bonus that wasn't on the listing :) ) so I've been trying to decide whether it's worth taking it out to use a 3-in-1 or keep it and do a stack of cards. Sounds like the DMA isn't that big of a deal then, now it just comes down to how original I want to keep it :)
I have both a 1000 and 1000SX. No keyboard for either. So I haven't tried restoring either. Any suggestions for those? I do have 1 monitor, a couple printers, and boxes and boxes of floppies.
Definitely have some suggestions! For the one without a monitor, you can use an RGB2HDMI for video. For keyboards, I believe that Cybernatic Systems on Tindie makes adapters... if not, there is a great TRS-80/Tandy 1000 Facebook group with lots of folks who have made adapters and other components. For storage, you can go with an XT-CF adapter to add "hard drive" storage! You should definitely join the Facebook group, lots of great info in there
At this point, you'd need to assemble your own, but occasionally there are folks who create these. It might be best to join the TRS-80/Tandy 1000 Facebook group for updates!
@@neomatrix4412 ah. I'd imagine so, but I think those upgrade CPUs are pretty rare. Also, keep in mind the TX only has 8 bit ISA slots. Might be best to acquire a 486 system instead.
So one thing I missed in my comparison: the 3-in-1 solutions do not have a DMA controller. For most cases this is not a big deal since the 3-in-1 card has SRAM, so not needed for refresh (video chip refreshes the motherboard RAM). Some use cases do use DMA (i.e. specialized disk writing software, sound cards). If planning one of these use cases, you'd want to go with the "stack of cards!"
Interesting! Nice reference there for Tandy 1000 owners. Very informative, thanks Chris.
Thank you! I love my Tandy 1000s!!
I built the original 3-in-1 card for my 1000EX. It isn't pretty, but it seems to work without issue.
Nice! It's a great card. Brings so much utility to the 1000 HX/EX!
Hey John!
3-in-1 v2 club represent! I need to use mine more, been too busy to enjoy my vintage computing hobby lately.
Same here! I haven't done much with the HX recently 😞.
Excellent video and work!! I don't have that conputer yet, will come back here one I one to my collection. Thanks for sharing!
Thank you for the kind feedback!
Nice to see you had so many options. Very interesting.
Thanks Hugh! Yea, lots of great options to expand these machines... which were a little bit harder to expand back in the day!!
Very useful as always, thanks Chris!
Thank you, Jim! This was a fun video to make.
Great video… I really need to get a v3 for my Tandy!
Oh yeah, it's an awesome upgrade!!
So, at present, I'm now aware of anyone building these cards, but the GitHub repos listed above in the description do include a bill of materials! Also, in addition to the 3 in 1 cards, there is also a 4 in 1, which includes a SmartWatch chip, but I don't believe includes a parallel port or second serial port. I've added a link above to the 4 in 1 repo.
A 3-in-1 v3 with with an ISA adapter for the upper slot would be perfect. COM1+LPT2 can fit on slot 1, COM2+CF can fit on 2, leaving 3 free for experimenting (ethernet / sound card / hercules video for 2nd display )
True! The bay is a little "small", so most conventional ISA cards won't fit. But I like the idea!
Unfortunately, it would be super limited both in physical space, and in available resources. With the V2 design, there are no available IRQs left on the expansion bus, and most of the upper address space is taken up with Upper Memory Blocks.
@@RetroTechChris Hi - we cant be to far away from V4 with ethernet and WIFI - a project for the Raspbery PI as a add on ??
@@georgemaragos2378 I think we might be out of IRQs! But I have gotten Ethernet on these using a Xircom Pocket Ethernet III connected to a Google WiFi access point :)
I am needing one for my 1000EX
They are great to have! If you are handy at building a card, you can grab the bill of materials, link in the description. Otherwise, you might check out the TRS-80/Tandy 1000 Facebook group to see if anyone is planning to run a batch of cards (link also in the description)
Also, I do see them occasionally pop up on eBay!
@@RetroTechChris I can do the soldering but not the chip flashing.
@@pitfalljerry you might be able to program the chip with a bootable floppy and XTCF software! If not, a ti866 plus will do the trick for flashing a chip!
@@pitfalljerry I asked in the discord if anyone has tried to flash without a programmer. Will see what we find out!
Hi Chris! New subscriber! I didnt know there was a 3 in 1 v2 ! I keep having to swap between my mouse and wifi to serial modem. Having two com ports would be great!
Hey Chad! Welcome to the channel. Yea, this card is GREAT. I can't recall if you are in the TRS-80/Tandy 1000 Facebook group... occasionally someone will do a run of cards... but if not, I presume you could build one too! A "perfect" card would have networking built in too, but my Xircom PE3 seems to help there. Anyway, glad you are here and looking forward to chatting more!
Thanks for the great video! Quick question - I know the Tandy Memory Expansion card also included a DMA controller. Is this a feature of the "bundle of cards" solution over the 3-in-1? I don't believe the 3-in-1 includes a DMA controller right?
You are correct! Here's the designer's take on why there is no DMA controller on the 3 in 1: "Memory refresh on the 1000, A, HD, EX, and HX is handled by the video chip. The video chip can only access the RAM on the motherboard itself, and not on any expansion cards. Tandy used the DMA controller to handle DRAM refresh for the expansion card(s). Since this design uses SRAM, it does not need to be refreshed, so does not need a DMA controller."
Also from the designer: "There are a couple of edge cases that depend on Direct Memory Access as well, such as some disk image writing software, but they are few and far between. Same with some hardware, such as a Sound Blaster, which 1) wouldn’t natively fit, and 2) would take away from the Tandy 3 voice sound that the system is known for."
@@RetroTechChris Thanks! I recently got a Tandy 1000 EX, and it actually came with a Memory Expansion card already (extra bonus that wasn't on the listing :) ) so I've been trying to decide whether it's worth taking it out to use a 3-in-1 or keep it and do a stack of cards. Sounds like the DMA isn't that big of a deal then, now it just comes down to how original I want to keep it :)
@@nathanbyrd873 that's awesome! Yea, I kept the stack of cards in mine until that 3-in-1 V2 got released... great card!
Great video! Know of anywhere to get the 3in1 v2 pre-built?
Sadly not at this time, you can ask in the TRS-80/Tandy 1000 Facebook group to see if anyone is building them!
There is nobody that I know of at this time, but if someone wants to pick up the torch, they are more than welcome to!
I have both a 1000 and 1000SX. No keyboard for either. So I haven't tried restoring either. Any suggestions for those? I do have 1 monitor, a couple printers, and boxes and boxes of floppies.
Definitely have some suggestions! For the one without a monitor, you can use an RGB2HDMI for video. For keyboards, I believe that Cybernatic Systems on Tindie makes adapters... if not, there is a great TRS-80/Tandy 1000 Facebook group with lots of folks who have made adapters and other components. For storage, you can go with an XT-CF adapter to add "hard drive" storage! You should definitely join the Facebook group, lots of great info in there
where you could buy this ?
At this point, you'd need to assemble your own, but occasionally there are folks who create these. It might be best to join the TRS-80/Tandy 1000 Facebook group for updates!
@@RetroTechChris is a 286 to 486 cpu card possible ?
@@neomatrix4412 this system has an 8088 CPU. It can be upgraded to a V20 to get 80186 compatible instructions.
@@RetroTechChris i mean the 1000tx
@@neomatrix4412 ah. I'd imagine so, but I think those upgrade CPUs are pretty rare. Also, keep in mind the TX only has 8 bit ISA slots. Might be best to acquire a 486 system instead.