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Annoucement: Hi-res graphics for TRS-80 Model 4P finally released!

T

TRS-Ian

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The TRS-80 support just continues :)

Available from my web site: http://ianmav.customer.netspace.net.au/hires/hires.htm

I am now am taking orders on this great new product, which is a modified version of the HRG I started selling in April, this one re-arranges the components on the PCB so it now fits inside the Model 4P Portable TRS-80:

DSCF1038.jpg

Here is how it compares to the old µLabs 5.1 HRG which it is based on:

DSCF1035.jpg

So it fits inside the motherboard cavity like so:

DSCF1022.jpg

Installation in the Non-gate 4P is easy with only 3 jumpers positions changed after plugging in the PCB and hooking up the fly-lead. Installing into the 4P gate array is even easier with one jumper on the HRG connector removed and just hooking up the fly lead.

DSCF1015.jpg

This video explains it all:


Cheers,

Ian.
 
Cool!!

Does it occupy any space within the internal modem slot area? I've thought about using that area for a WiFi board.

Now, do you think you could make an internal FreHD + HiRes + WiFi upgrade for the 4P for your next amazing trick? :)
 
The Model 4 board is based on Grafyx 4.2. The Model 4P board is based on Grafyx 5.1. What is the difference between Grafyx 4.2 and 5.1, and wouldn't Model 4 users want to use the (presumably newer) 5.1 board too?
 
The 5.1 is the same as the 4.2 (exact same parts) just the layout is changed so that it fits inside the confines of the 4P.

I'm glad someone asked this question because the differences have been a source of frustrations since my first GX 4.2 prototype arrived. Having not owned a 5.1 I assumed the 4.2 fit in all machines - bad assumption. The 4.2 only works in a M4NGA (and with a modification, on the M4GA and 4D). You need to re-arrange the parts in board so that it fits inside a 4P. When µLabs designed the GX 4.2 only the M4NGA was on the market and the 4P followed some 9 months later so they couldn't have possibly known their 4.2 wouldn't fit in the 4P. Once you re-arrange everything so that it fits in the 4P, then the board no longer fits into the M4NGA. There is no getting around this problem on a board with 32 chips. (Tandy got around it with their board because it's tiny by comparison.)

So this explains why both the 4.2 and the 5.1 were on the market in parallel and when you ordered it from µLabs you had to fill out a detailed order form so they could identify which board to ship to the buyer.

Interestingly, when RS redesigned the M4NGA into the M4GA the new position of the HRG bus connector means that the 5.1 does fit in and works in the M4GA and 4D.

SO... I had to decide, work out how to make my improved GX 4.2 fit in a 4P, or get the whole PCB re-designed to 5.1 layout so that it will fit in the 4P. I looked at cables and mounts but eventually level headedness prevailed and with the help of my buddy P.H we nailed it. This way people who have a modem or a FreHD installed in their modem slot are not affected.

Twice the work but I think it was worth it and I'm hoping everyone who was been waiting for a 4P HRG will get behind the project.

Ian.
 
@TRS-Ian You may have mentioned your reason for this before, but since the 26-1126 fit all M4s, why did you choose to reproduce the Grafix boards and not the RS board?
 
Trust me it would have been my choice as well (1 PCB design, and only 15min assembly time vs. 2 PCB designs and around 45min assembly time) but the fact is RS got away with it by combining 75% of the TTL logic required into a single 40-pin Gate array called a PS IO chip. These chips must have been custom made for Tandy as they are unobtainium now.

Actually, there are 8 still in circulation, Lowen found them but the seller wants a kings ransom each for them. And there are only 8. Therefore the cost to do the reverse engineer of the 26-1126, get 8 PCBs made (a small number, as I usually buy them in qty of 50) would be an expensive project. I don't think anyone would want to pay double what my current HRGs sell for but that is the reality of what I would need to ask for them.

Now, if someone can turn up a reasonable qty of PS IO chips (say 25 or more) at a reasonable cost each I'd be more than happy to bank roll the project but I dare say this is one instance where the chips are not just hard to find, but impossible to find.

Fortunately the µLabs designs use 74LS family TTL which is easy to find and I am very familiar with. Though some of the chips are difficult to find (like the 74LS10) they are still out there and only adds to the fun of making these HRG boards. It's only not fun when you can't find a part anywhere (like the aforementioned PS IO).

Ian.
 
Just thinking out loud here: Could you afford to sell these sorts of things with a $20 FPGA replacing most of the logic? Possibly combining multiple functions in there (HRG, HD, etc.?) to spread the pain? It would be a surface mount part, which would likely mean spending money on assembly instead of spending time doing the assembly yourself. That would be my preferred approach, but I don't know whether it can be done economically at the pricing and volume of the TRS-80 market. $20 buys a Xilinx Spartan 6 with 64kx9 of dual-port block RAM, most likely eliminating the need for any external memory for buffers, ROM, etc. It would need an SPI EEPROM chip for the FPGA configuration, a couple of DC-DC converter chips for core and I/O voltages, and conversion between 5V TTL and 3.3V CMOS I/O. But it would eliminate any glue logic, RAMs, microcontroller chip, etc. at the same time. Board size could probably be reduced.
 
NF6X said:
Just thinking out loud here: Could you afford to sell these sorts of things with a $20 FPGA replacing most of the logic? Possibly combining multiple functions in there (HRG, HD, etc.?) to spread the pain? It would be a surface mount part, which would likely mean spending money on assembly instead of spending time doing the assembly yourself. That would be my preferred approach, but I don't know whether it can be done economically at the pricing and volume of the TRS-80 market. $20 buys a Xilinx Spartan 6 with 64kx9 of dual-port block RAM, most likely eliminating the need for any external memory for buffers, ROM, etc. It would need an SPI EEPROM chip for the FPGA configuration, a couple of DC-DC converter chips for core and I/O voltages, and conversion between 5V TTL and 3.3V CMOS I/O. But it would eliminate any glue logic, RAMs, microcontroller chip, etc. at the same time. Board size could probably be reduced.
Click to expand...

I was thinking the same thing. Plus you have the added advantage of modifying the design and then being able to 'redeploy it' without any soldering/desoldering.
 
3pcedev said:
I was thinking the same thing. Plus you have the added advantage of modifying the design and then being able to 'redeploy it' without any soldering/desoldering.
Click to expand...

True, but an end user would generally need to download a *HUGE* ISE-Webpack distribution and buy a programming cable (such as one of the Digilent ones) to reprogram the board in the field. That's not necessarily a deal-breaker, but it'll be beyond the pain threshold for many (most?) potential users.

Not that I would mind, however, since mucking about with Xilinx FPGAs is part of my day job. ;)
 
Very cool! The board and components look pretty straight-forward, do you plan on selling a kit or even the PCB + instructions?
 
It's interesting to discuss design alternatives, but personally I think the approach Ian & co took was the most sensible because:

* It's an almost exact implementation of a proven design. While theoretically the Tandy board's gate array could be reverse engineered (i.e. using the details in the 4P Service Manual as a starting point) and re-implemented in a modern programmable device, there's a lot more work involved and always the chance that something's not quite right.
* It uses readily available components and a construction technique consistent with the era.
* The Grafyx product was the more popular board for the Model 4 (ref: http://www.trs-80.org/model-4-grafyx-solution/) probably due to its lower cost and longer sales cycle. With this remake you get an almost exact copy of what most people were using during the day.
 
NF6X said:
Just thinking out loud here: Could you afford to sell these sorts of things with a $20 FPGA replacing most of the logic? ...
Click to expand...

Mark McDougall looked at doing something similar a few years back; see http://members.iinet.net.au/~msmcdoug/trs80/grafyx.html for his page. There would be a number of things one could do with a small FPGA, but, there again, someone has to do it that has the software setup to work with the things. A pre-loaded serial EEPROM and an FPGA with level converters for 5V wouldn't be very large, no.

I like Ian's approach on a number of levels. It is easily buildable with SSI TTL parts and a static RAM, for one. It's way more vintage than an FPGA solution, number two.

There is one fly in the ointment, though: the original Grafyx Solution only had 20KB of RAM, and more than likely some programs that were designed to work with either of the two hi-res boards use the size of the RAM (one thing that is easy to test for) to select whether the 26-1126 support is selected or the Grafyx Solution support is selected. I have one of those programs, ANSITerm, in my list of things to disassemble and reverse-engineer to see how it does its board autoselect and patch in a manual selection ability. As Richard derived his ANSITerm IV that was sold through CN80 from the ANSITerm that Brad Mettee wrote and that I cleaned up and released back in 1990, it would complete the circle, so to speak, to go into that code.... I'm looking forward to doing it, just haven't had enough 'round toits' to get it done as yet.
 
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Bonjour
Google translate
You know the hardest for create type cards:
http://www.prof-80.fr/grafix-5-1/prototype-grafyx-5-1
http://www.prof-80.fr/grafix-4-2/graphix-4-2
http://www.prof-80.fr/kit-graphics-26-1125/compatible-kit-graphics-26-1125
http://www.prof-80.fr/doubleur-lnw-80-5-8/prototype-doubleur-lnw-80-3-5-8
http://www.prof-80.fr/doubleur-percom/prototype-doubleur-percom
http://www.prof-80.fr/hifi-color/prototype-hifi-color
http://www.prof-80.fr/coupleur-cp-m-omikron/prototype-coupleur-cp-m
.......

This is to obtain the information! It is easy to criticize the achievement with a pencil, but few people who use the soldering iron or when providing information.
To get a picture of a "PCB" or a manual, I must wait several months
thank you for responding to my request on Newclock-80 M1 card :confused:
Pascal

Vous savez le plus difficile pour créer des cartes types:

http://www.prof-80.fr/grafix-5-1/prototype-grafyx-5-1
http://www.prof-80.fr/grafix-4-2/graphix-4-2
http://www.prof-80.fr/kit-graphics-26-1125/compatible-kit-graphics-26-1125
http://www.prof-80.fr/doubleur-lnw-80-5-8/prototype-doubleur-lnw-80-3-5-8
http://www.prof-80.fr/doubleur-percom/prototype-doubleur-percom
http://www.prof-80.fr/hifi-color/prototype-hifi-color
http://www.prof-80.fr/coupleur-cp-m-omikron/prototype-coupleur-cp-m
......

C'est d'obtenir les informations! Il est facile de critiquer la réalisation avec un crayon, mais peu de personnes qui utilisent le fer à souder où qui donnent des informations
Pour obtenir une photo d'un "PCB" ou un manuel , il me faut attendre plusieurs mois
merci de répondre à ma demande sur la carte Newclock-80 M1
 
Can people advise me what sort of software they'd like to see for their HRG cards?

I'm planning to update my HRG page and want to make sure the software that people want is available to download.

(It takes some time to prepare software as when I find some from various archive sites its either incomplete or the system requirements are such that it doesn't work without mods, updates, specific BASICG versions etc.)

Also talk to me about what people would look for in a kit version and I'll look into the feasabilty of kit versions of mt HRG boards for those I think are competent enough to assemble their own HRG boards.

Cheers,

Ian.
 
Hi everyone,

I've spent today updating the web site with more new hi-res products to buy and software to download:

http://ianmav.customer.netspace.net.au/hires/hires.htm

Highlights of the update:

New hardware: Traditional 20K GX 4.2 and 5.1 HRG boards and Model III kit for electronics specialists (or those certifiably insane)

New software to download: Life, Spiro-Graph, Pascal Routines, CN80 Hi-Res Utilities, MagicDraw, and Multidos 5.11 and Hi-Res Basic.

I also updated all the photos to clearer ones to really appreciate the sharpness of the high resolution.

Cheers,

Ian.
 
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