Most liked posts in thread: Researching the TRS-80 Coco 1/2/3 repairs & upgrades and differences between them.

I'm not going to buy it, I want to restore and upgrade a Coco model 1 myself, but I wanted to show a picture of a Coco model 1 for sale, upgraded to Coco 2 specs, but with the later Coco 2 revision keyboard, not the "melted" keyboard like mine will have. But I think the "melted" keyboard on the Coco 2 I am getting will look more vintage and go with the older metallic case better anyway, just like the first model 2 with the model 1 style case above that is beige.

 

The TRS-80 Color Computer 2 temporarily takes the place of the 800, and possibly permanently depending on how soon I run electricity to my new, essentially workshop/computer lab/office, a man-cave, as this will be a private office,etc, anyway. I go to the customer in my business, they don't come to me.

 

Well, the MOOH board, as far as I know, is currently in production and I have one on pre-order. So I ended up getting the SuperSprite FM+ board first instead, along with a CPU pull-up board kit since I don't have the newer SAM chip, this takes care of the new addresses missing on the old SAM chip, that are required (along with 64K and extended OS, at least on the Coco) to use the new SS FM+ board. I also got their Oojiflip board kit, which allows two multi-pak's plugged in at once as an alternative to an MPI multi-I/O or new similar re-manufacture. All are available in kit or built form and the SS FM+ has a couple of options too, and can be bought in kit or built form. I went with the built SS FM+, since it's nearly the size of the Coco mobo and I have enough projects. But I went with kits on the others since they are small boards, to save a bit of money.

I've been doing some reflecting, after looking at the invoice, and questioning why I was so determined not to pay over $100 for another 8-bit computer, but am perfectly willing, without second thought, of paying more than $200 ($300 with other purchases for it) for an upgrade to that same computer...I've discovered some strange psychological tic in my thinking when spending money on this hobby... IIRC, the MOOH board will cost me over a $100 too!

 

Been a while since I added anything to the CoCo thread but I thought this would be worth adding. The CoCo's while pretty robust it seems the Achilles heel was the keyboard membrane. Similarly to the Atari membranes they were never really designed to work for 40 years and depending on use in the intervening years are failing.
My CoCo2 was one such machine, when I bought it a couple keys didn't work. I stripped the keyboard and tried to examine and clean it. This actually made things worse! so I bought conductive paint and tried that, that didn't help. So I ended up using the CoCo technical repair manual for the keyboard matrix to determine which tracks were failing. So I ended up using stripped Kynar wire held in place with very thin strips of copper tape. This enable me to get a working keyboard. It's not pretty but getting a new replacement mylar is impossible.
This is where a guy called Mike Rojas in the States comes in. He has designed a PCB with low profile SMD tactile switches, 3D printer spacer and a flexible PCB connector and new screws. He has produced kits for the CoCo1, 2 and CoCo3. He is on the Tandy CoCo Facebook group if you are looking for him. Needless to say my kit left the USA yesterday for only $25 plus shipping it was a no-brainer to try and keep this bodged membrane as a reserve for any other CoCo I find. This is one area that the Dragon improves on the Tandy machines as they have Stackpole keyboards like the Oric Atmos.
Anyway it's worth sharing with the group.

 

I figured I'd show my new arrival in this thread since I already announced it with a picture in "What's new pussycat too."


First impressions of my Coco 2 "melted" keyboard model is that the case it better than I thought, what I thought was slight yellowing and it would need a retro-brite, looks to me to just be a bit of dirt I can clean off with some glass cleaner and a cloth. It's in fantastic shape otherwise, though it is missing two of it's four rubber feet on the bottom. The same square kind that are on Indus GT and CA-2001 drives.

The "melted" keyboard is certainly a step in the right direction from the chicklet keyboard of the Coco 1, but it's feel does remind me of my 130XE's keyboard; a bit "mushy." But the keys themselves seem sturdy and not flimsy like XE keyboards. I think I may decide not to use this Coco 2 as parts for a Coco 1 and just have both, and get parts to upgrade a Coco 1 separately.

I'll open her up later to make sure there aren't already mods or upgrades that the seller may have been unaware of...

Below are a couple of pics for size comparison to it's Atari contemporaries and a close-up.

 

So I started taking screws out to open it up, and there was one screw still holding the case together that I couldn't find, until I realized it was still hidden under the warranty sticker! This machine has never been opened! Upon opening it I see an inside case and motherboard that look factory-new, not one speck of dust or dirt anywere! And it's got an empty socket just waiting for the Extended Basic upgrade, or that's for the OS9 OS, not sure yet. I have to look up the 8 ram chip numbers to make sure, but I think this is the 16K version, I think the 64K version came with Extended Basic installed. But I do have to check and the chips don't give an indication with the last two numbers being 16 or 64. I can't locate a 16K/64K jumper on the mobo though, which in some videos they have shown for upgrading ram, so this may be a 64K version stock.

 

Yes, the Dragon is a clone that is about 95% compatible, and actually I remember in my research somewhere that with a slight mod of the OS or slight hacks of the software, one or the other, both can run each other's programs.

There was a version of the Dragon by a company called Tano here in the states for a while. Of course the TRS-80 Coco was sold in the UK and all or part of Europe, I know France for sure. That color Genie you showed earlier is actually a clone of one of the original TRS-80 machines (not Coco and used the Z80 processor instead of the 6809)model I and III's. They ran CP/M.

Below is a picture of the 600XL mobo,minus it's PBI port, next to the Coco 2 second model release. I can't wait until I get a Coco 1 and compare it to the 1200XL, I think their sizes will be very close, maybe with the Coco 1 being slightly deeper by an inch. Of course I could look up the dimensions of each, but that's no fun.

I haven't been able to test my Coco yet, as these things don't have power LED's to even let you know they are on (many people mod them for and LED and I will too) and it is only RF out, like the Atari 400 and the U.S. 600XL. This is the Coco 2 model from about '82-3 just when the 1200XL and 800XL were aroun. I can't believe they don't at least have a monitor port, but it was RF out only,even for the 64K versions, until the Coco 3 when they finally gave composite out and RGB out. So there is an easy video/S-video mod I will do, just like I'm doing for the 7800.

I had an in-line RCA to coaxil RF adapter but I can't find it! I may just end up temporarily "hot-wiring" it between it and the TV to test it...

 

Well, I swapped out the 16K ram chips for some 41256's. I could only find 5 4164's and then remembered the rest were on the 16K 800 ram board I was modifying for 64K when I got the Incognito. It's in my glass case, difficult to get into now.

So I knew 41256's would work as 4164's and I have plenty of them too now since I reverted my 1200XL back to 64K internal since I have the PBI and an external 512K on the Syscheck board.

And since I couldn't find my RCA2Coaxil adapter, and deciding not to wait until I did a video mod, to make a hacked-together temporary RF cable to my TV. And PRESTO! I have a MINT condition 64K Coco 2 only needing the Extended Basic rom and that video mod I will do this weekend. So it was just some IC's that needed to be re-seated in their sockets!

I tell you, first controllers coming to me for free, then a deal for a not-working-right Coco 2 that looks in good condition, then find out it's in pristine condition after a good cleaning, and a perfectly pristine interior...a perfectly new working motherboard after re-seating the IC's...using the same type of ram I have on hand...an eprom burner for my Atari that can burn the ROM I need for the Coco 2...a new shop/lab/office trailer to make more room for my kit...this was no series of coincidences, this was destiny.

I'll just have to have both a Coco 1 I restore and upgrade and a mint Coco 2. If it were a well-used machine with a yellowing case like I saw many of on ebay, then I would use it as a parts machine.But this thing is in mint collector's condition with no refurb or restoration needed. So I will keep it and keep it that way. I just noticed too, that the name plate still has the protective plastic over it and I'm leaving it in place because even that plastic film has no scratches or nicks and is perfectly invisible! I only discovered it by touch myself!

My RF hack-job:

My working TRS-80 Coco 2 already upgraded to 64K, maybe 256K if I find there is a way with these IC's:

My mint condition TRS-80 Coco 2 after a good cleaning with a cloth and window cleaner:


.

 

Below are some facts and specs on the TRS-80 Color Computer 1 & 2.

_________________________________________________________________________________
The Color Computer was part of Radio Shack’s attempt to diversify their computer product line. Costing only $399.00 for its basic model, it was designed to compete with other lower-cost computers, such as the Atari 400 and the Commodore VIC-20. But the Color Computer inspired a wide range of uses, multiple support magazines, and a vibrant third-party software and hardware market. The Color Computer series was probably the best selling of Radio Shack’s own computer models.



Color Computer specs

The Color Computer used the Motorola 6809. (Early rumors said it would be called the TRS-90 because it lacked a Z80.) This was unusual because most other inexpensive computers at the time (and some expensive ones such as the Apple II) used the MOS Technology 6502. The Motorola 6809 was a highly regarded processor with many design features that were more in line with a 16-bit microprocessor. Even though the 6809 in the Color Computer ran at only 0.895 MHz, the design meant that it was comparable to the 2.03 MHz Z80 in the Model III.


Specifications

The Color Computer had good specifications for a home computer at the time:

-a Motorola 6809E processor running at 0.895 MHz
-a 53-key “chiclet” keyboard, with arrows, BREAK, and CLEAR keys
-uppercase-only text mode with 32 column by 16 lines
-eight graphics modes, including 64 by 32 with eight colors and 256 by 192 with four colors
-one RS-232 port (the so-called bitbanger port)
-sound output with a 6-bit digital-to-analog converter
-1500-baud cassette I/O for storage
-a slot for plugging in cartridges known as “Program Paks”
-initially 4k expandable to 16k then later a 32K and 64K

64K NOTE: The reason BASIC memory is the same for 32K and 64K is due to legacy designs. The 6809 processor can only address 16-bits of memory space (64K). The BASIC ROMs started in memory at $8000 (32768, the 32K halfway mark). This allowed the first 32K to be RAM for programs, and the upper 32K was for BASIC ROM, Extended BASIC ROM, Disk BASIC ROM and Program Pak ROMs. Early CoCo hackers figured out how to piggy-pack 32K RAM chips to get 64K RAM in a CoCo, but by default that RAM was “hidden” under the ROM address space. In assembly language, you could map out the ROMs and access the full 64K of RAM. But, since a BASIC program needed the BASIC ROMs, only the first 32K was available.

When 64K upgraded became available, the original BASIC would still only report about 24K free since it had never been modified to make use of the extra memory. Thus, typing “PRINT MEM” on a 32K CoCo 1 shows the same thing it does on a 512K (or greater) CoCo 3.

___________________________________________________________________________________

Back to me me talking:


After I installed my 64K, but still only standard BASIC 1.2, minus memory for cassette, serial and some other I/O, when I do a "print mem" command it shows I have about 31K available instead of the 24K available for Extended Basic 1.1! So I will lose even more Basic ram space once I install the extended Basic rom chip!
But since it show 31K available under Basic, that means it's seeing 32K ram so most likely my full 64K is working, I just need to load up a 64K machine language tape program to know for sure.

Also, it suddenly occurred to me, after reading that any standard cassette recorder could be used with the Coco series, even though they had one specifically designed for the system, that some of those cords I got with the Coco joysticks and mouse are actually a cassette cable and probably a serial cable!

 

Great discoveries being made, Matt!

I lurve how a new model on the scene sets in motion all this research and unearths nuggets of interesting information.

It always amazes me just how ingenius the hackers and modders are too and I reckon the sky will again be the limit with this Coco, mate.

Keep us posted!

 

Continuing my research and learning what devices and peripherals the Coco's had legacy wise, and modern home-brew, One thing I've learned is the TRS-80 Color Computer (line) is a strange beast. It's modular, like Atari 8-bit and Commodore Vic-20/C64 computer lines, So one can buy the basic computer and add on via peripherals and other devices. But it's architecture is more like the Apple II line, with dumb peripherals that required controller cards, but since it's modular, it's more like the TI-99/4A with it's expansion box or the proto-type Atari 1090 PBI expansion box.

But not quite, as it's not done with internal cards like and Apple II or the other's expansion boxes, it's done externally, through the TRS-80 Coco's expansion/cartridge port (similar the PBI/ECI/Cart ports on Atari 8-bits) with a multi-pack device, with four external "cartridge" positions for you to plug in your floppy or hard disk controller, or modem/RS232 pack, other port expansion like centronics parallel adapter module. And controller packs came with just about every device like graphics tablets or high-resolution mouse adapter packs.

You end up with a bulky monstrosity with huge "paks" sticking up out of the multi-pack device right on the side of the comoputer, and any serious user would still have more peripherals controllers and cartridges than the 4 slots, so power-downs, swapping, and restarts had to occur.




There was a model for every model of Coco, and even some after-market ones with up to 6 ports.



"pack modules" are huge bulky things, like two 5200 cartridges stacked.



I much prefer Atari's smart peripherals and the SIO, honestly, with the occasional PBI/ECI device.

The Coco's 6809 CPU runs at less than 1Mhz, and even with advanced features usually only found in 16-bit CPU's, because of it's 0.8xx clock rate it's hardly better than the 1Mhz original 6502 in the ViC-20. They say it compares to a 2Mhz Z80, but I also know that the Atari's 1.77/1.79Mhz 65co2 compares to the 4Mhz Z80 in the Coleco Adam, so that tells me it's exactly what it seems, a CPU half about half the speed of the Atari's.

Though with the last model of Coco 2 a newer version of the 6809 was used and had an undocumented "turbo" mode that can be poked to put the CPU into 1.78Mhz mode.

The Coco's VDG (video display Generator) is closer in ability to the VIC-20's VIC I chip than the VIC-II or Antic. Again, in the last model revision of the Coco 2, a slightly upgraded version included lower-case text that Coco's before didn't have. But it still only produced 32-column x 16 line text screens. It has nearly as many graphic modes as the Atari. Bitmap mode included a 9-color palette, but only the lowest resolution could display all 9 colors. the other modes were limited to 2-4. It's high-res mode, like the Apple II and Atari's used artifact colors, but the Coco could only do orange, blue, black and white, while the Apple II and Atari's NTSC artifacting can achieve 8-9 colors..

Resolution graphics store 8 pixels per byte and are available in 128×64, 128×96, 128×192, and 256×192 modes. Color graphics have 4 pixels per byte and are available in 64×64, 128×64, 128×96, and 128×192. The maximum size of a bitmap screen is 6144.

The Color computer has two PIA's (like the upgrade I just did to my 800!) that control all I/O through the cassette. Serial (RS232) and worked with a simple ADC/DAC 6-bit chip for that analog joystick ports and keyboard. Unfortunately the Coco didn't have the advantage of a dedicated chip like Pokey for keyboard and high-resolution analog pots, so the Coco's joysticks and mouse, with the 6-bit chip, only had a resolution of 64x64!

This was fine for games and using the mouse or joystick to move a cursor around a 32x16 screen for programming or word processing (who'd want to do 32-column word processing with only upper case text anyway? Lower case was represented by inverse video). So high-resolution control packs were required for the otherwise perfectly good mouse and joystick to be used to their full potential. You then plugged them into a new port on the control pak! But only a high-res graphic art program with artifact colors took advantage of this before the Coco 3.

I certainly don't plan to do art on my Coco 2 with it's color limits, so I am going to convert the mouse for use with the Atari 800. I still have analog joystick just as sensitive to move the cursor around on-screen with the Coco anyway.

Coco sound chip? Terrible. yet another use of the expansion port was an Orchastra-90 pak with a better sound chip.

Of course these days there are plenty of internal and external upgrades for the Coco line including a VGA board for VGA output that includes new graphic and text modes (64 or 80 column), sort of like a cross between the VBXE and Sophia 2 on the Atari. Memory and speed upgrades and OS too. So there is plenty for me to mod and upgrade and bring this Color Computer 2 of mine up to par with Atari's and all their cool modern upgrades.Unfortunately, while modern upgrade hardware on the Coco line is on pace with the Atari's, the home-brew software side is absolutely dismal and little takes advantage of the new hardware, as the few home-brew games that have come out, want to reach the lowest common denominator and go unused, like the VBXE. But even so, new games since the 80's can be counted on both your hands for the Coco line, it seems,

 

Again, it's riveting stuff this as I had no idea what form, shape or design the Tandy Co Co's went for in terms of expansion and peripheral boxes.

They are quite something to behold in their variation and, at times, bulk.

All I recall were the basic Tandy colour micros on the shelf or in the window of the same name store and me thinking... what strange beasts are these and then someone saying "They're a bit like a Dragon" but I knew next to nothing as they were rarely (if ever) covered in the mainstream UK computer mags - would you agree, guys?

I got the impression that anything you wanted for them would be, like the Atari, quite expensive and very much proprietary so kinda steered well away and never ever knew anyone who owned one so they remained... exotic beasts.

You are opening up new frontiers to many of us on here, Matt - thank you.

The specs, whilst not being amazing, are nevertheless interesting as I did not have a scooby do.

 

You are welcome. By the same token they were always strange beasts to me too, just like the Coleco Adam too. I saw commercials for the Adam back in the day, the TV stations were flooded with commercials for it after it was discontinued and they were liquidating, but of course the commercials made them a going concern and seem like they were popular and well supported. But at the time I wanted nothing to do with turbo tape drives, I wanted a disk drive, and I couldn't afford even the fire sale pricing because they only sold it as a system including the printer, and had too, since the PSU for everything was in the printer! So luckily I avoided a dead system, riddled with bugs and failures, with a VERY limited software library of it's own, and then the Colecovision's game library as they were compatible, but even the Colecovision has less than a 100 titles, similar to the 7800, Lynx and Jaguar libaries because of the video game crash of '83/84. So it remained mainly a strange beast and curiosity to me, but I want one now for that very reason.

I remember the TV stations being flooded with commercial with and without William Shatner too, for the VIC-20 not long after the C64 came out, and they were unloading overstock and like Coleco and the Adam, were acting as if it was the latest-greatest that would have software and support for years to come!

This was also true of the TRS-80 Coco's. Though I would rather have the Coco 3, but they sell for $500 like the 1200XL. In the Coco's case though, I was an avid Radio Shack shopper as a youngster, so I remember always seeing some model of the TRS-80 Coco on display, and it did catch my attention because it was being demonstrated to someone at the time and it had the mouse and GOS environment, and pretty much looked like an Atari ST or Amiga quality computer on the surface. But even though they were meant to be low-end models, they were still selling them for $100-200 more than The C64 or Atari XL/XE's. So I tended to ignore them and only the Coco 3 caught my eye when it was released, but by then I had made my choice with the 130XE and was building a system and library for it.

So the Coco's remained a strange beast and mystery to me as well. I never knew anyone who owned it or the ADAM. I didn't even know anyone who owned an Atari. my friends all had C64's or Vic-20's or Apple II's and one had an IBM PCjr! So again it was another 8-bit micro that I always wondered about, but was satisfied with my 130XE, and actually felt it far superior to most other 8-bits and was proud of the fact even if friends scoffed. They stopped scoffing when they saw the Atari in action, and soon wanted to play it all the time.

Of course as many of you know, I had been planning on a C64, and if time and space and money allowed, followed with an ADAM, or BBC micro, or TRS-80 Coco, and fate or destiny just seemed to step in and put Coco stuff in my lap. Honestly I'd still rather have a C64, but they are just to damned expensive anymore, even though there are 100 on sale on eBay at any given time! Just a couple years ago you could get one for sometimes less than $50! Of course this is true of many vintages systems today.

The Coco's don't have a huge software library either, it seems like just a couple hundred commercial/semi-commercial programs were published for it, and about a quarter to one third are 16K cartridges from Tandy itself. But, I have discovered that it, and the Dragon 32/64 can be modded to use the other's software, or at least hacked versions of the software. And I have to start looking into Dragon Software, as I might just decide it got better software released for it, maybe even more? I might just turn this puppy into a Dragon full-time. I might not have too though, it may be a plug-in module. I have to look into it more. In which case I can have the best of both worlds and 2 systems in one! And now that @Vyper68 is getting a dragon, we can compare notes maybe in this area and help each other out.

 

All very stimulating and illuminating, Matt, as my knowledge of systems such as the Colecovision/Adam and Coco is virtually nil so all these extra bits of flesh you keep adding to the bones is really interesting and yes of course you and Richie will be able to bridge your know how and growing expertise as you investigate potential software successes and perhaps even get your coco breathing fire...yet!

Exciting times, fellas.

Never better to be in to retro micro!

 

It will be good to compare notes on your CoCo with my Dragon. I don’t have a massive amount of software currently but some of the Dragon’s library is very good. The Battlezone clone ( Rommels Revenge ) is excellent and that is Tandy compatible. Design Design also released a game called Dark Star which is also very good. There are a couple of games called BackTrack and Eddie Steady Go! which are good and may be worth checking out.
As far as hardware goes I have built a cartridge port extender which allows a cartridge to be fitted internally while still allowing access to the cartridge port from outside. Handy if you have a 32KB RAM cartridge and want to use a disk drive. Talking of disk drives I have built myself a disk drive interface and have been using it with my Gotek drive this week, so it makes it easy to save programs as opposed tape. I have a CasDUINO that enables me to load .cas files from MSX and Dragon’s so I have access to the Dragon cassette library as the Dragon Archives have nearly all the tape software released.
Finally I picked up a cartridge for the Dragon called DeMON which is a machine code Monitor program which worked fine. I opened the case and popped out the 4K ROM and fitted an 8K EPROM will Dragon Data’s AllDream assembler/debug software. I am waiting on another 8K EPROM and that will enable me to burn the DaSM/DeMON combo. So I will have saved myself a fair amount of money compared to buying DaSM/DeMON on feeBay.
Last thing is now I have the replacement power board fitted I am overhauling my original Issue 4 power PCB replacing the capacitors and voltage regulators with modern replacements. So hopefully when finished it will be more stable and reliable.

 

Have you looked at the CoCo VGA @M.D.Baker ? I have put my name down on the waiting list for one as they fit Dragons as well.
There is a PAL CoCo2 on eBay right now that I’m watching which hopefully I will be able to pick up for a reasonable price, as well as bidding on a very sorry looking Dragon 32 so I’m full on 6809 right now The CoCo is a 16KB model but there is no indication if it has been updated to 64K. So it will be interesting to see if I get it. The Dragon is a really sorry looking loft find so it might be a good candidate for the D.I.Y 64KB upgrade if I’m successful. I know Dave expressed an interest in getting a Dragon, it might need a new power board so it can use a standard 12V PSU.

 

Well if I go ahead and get one for my little Welsh wonder Matt, we can compare and discuss

By the way I heard from Tormod about the 32KB upgrade and uDrive a couple of days ago so he is still active. Have you heard anything from him?

Loosing the bid on the Dragon so going all in on the CoCo2 now.

 

I just checked my emails again and no, no response from him yet. I sent one about a month and a half ago and another about a week ago.

Good luck on the Coco. Mine was only 16K without extended basic rom, I had dram on hand to do the 64K upgrade and I needed a 28-pin adapter board I got from the Zipster site which came with the extended basic rom, so I didn't have to burn one.

 

I missed out on the Tandy CoCo2 ( it went for £122 ) so I picked up another Dragon 32 for £50 instead. It has an earlier serial number than the one I currently have, so I am hoping that (a) it works as it's the old untested chestnut but in this case I can see it's likely to be true as there is no PSU with it and (b) it is one of the earlier boards with the 8 half faulty 64K chips which you can swap with working 64K chips. That would be preferable that cutting and bypassing tracks on my current Dragon. Then I'll start saving for the CoCo VGA board.

 

I was thinking of getting a Super Sprite FM+ for my Dragon but still pondering it. I have a 6309 already so I’m good to go on that front.

 

I think it's going to be good. I'm hoping that eventually there will be some drivers for it that will be able to emulate Coco 3 graphics (since SSFM+ graphics are better)and in conjunction with the MOOH able to run TurbOS-9, be able to run Coco 3 software, as well as getting it's own homebrew software of course. Remember, it also has a SCART output that the video can still be sent through the FM+ from the standard OS when in that mode, so it's another better video out option if, like me, you want to keep the VDG socket available for an exterior character set and font board. The VGA board does to an extent with it's new VGA modes, but nothing compared to the SS FM+.

Another thing I'm learning is that although I don't care much for most Coco peripherals going through it's cart/MPI port, especially when they are dumb devices that require these large controller boards plugged into the side of the machine to work, the stuff that Atari smart peripherals have built-in to them. And I prefer Atari's SIO and Commodores serial ports for standard peripherals.

But, I am learning that the Coco's (I assume the Dragons have the same port) serial "bit banger" port that a few peripherals like the cassette drive and some modems use, are very much like the Atari's controller ports, and both have PIA's controlling them and can be used for lots of different devices too, but it was easier and faster to use the MPI (just like the Atari with both it's SIO and PBI/ECI) so not used as much.

Yet Coco serial ports with PIA's controlling them, like Atari controller ports, are full of possibilities with I/O and communication interacting with other machines not made specifically for the system, like my project of using controller ports and Atarilab Interfaces for prototyping and research and stuff like taking control of a robot I want to build.

I upgraded to dual PIA's on my Atari to add more controller ports for this purpose, and the Coco/Dragon have dual PIA's built in from the start, but only one serial output they control. Yet the possibility is there to add more, and I could have the Coco and Atari networked through their PIA controlled ports very easily indeed!

I know that the other video upgrades like the VGA give you new modes too, but can you use those modes and character sets with legacy software? With the external (from the VDG, not the Coco/Dragon) character/font board it is made to work with the original graphic and text modes, they are compatible and you can run even legacy software in whatever new font you choose that the board comes with or you program to it.

That's part of my reasoning for choosing the External Character/font board and SSFM+ over a VGA board.

The reason I chose the MOOH over the Coco SDC was the extra features built into it too, beyond SD card disk emulation.

It just seems to me that the Dragon community are putting out better upgrades with more upgrades per board in combination, where the Coco community is making boards that do just one or two things, add just one or two new abilities to the Coco/Dragon and Dragon/Coco upgrades throw in a lot more and obviously with the SSFM+ are just pushing the envelope of the entire system and not just modern media and video solutions like Coco/Dragon devices.

The Dragon first, but Coco compatible upgrades are more like upgrades for the Atari 8-bit that include lots of features and really take the machines to beyond the next level, with full legacy compatibility still.

I'm definitely really liking the Coco computers for all the legacy and modern upgrades and add-ons and peripheral/media and controller/input device options they have available, just like the Atari 8-bit. I still have yet to see if I'll fall in love with it's processor, graphics, OS's, languages and software too.

But the combination of internal upgrades and external one through the MPI port really make me feel right at home on the hardware tinkering side, just like the Atari and it's internal upgrades and PBI/ECI and cart port upgrade options. That's one of the reasons I'd planned on getting a C64 first, because it's the same. I am including both first and third party gadgets available for these systems.

Oy, do I ramble on...one sentence from you and I write a term paper in response...sorry

 

DASM needs the “@“ to define labels. The other 6809 assembler doesn’t need that. It’s just a quick of the program.
I have been reading up on MAC65 this morning so I may try and convert it to the Atari.
Even though it is a very simple program to fill the screen with characters, the speed compared to a BASIC program is impressive. Now I know why games were written in machine code.

 

I rarely touch assembler these days, I did code in 6502 and used to PAL fix Snes PAL protected games in 65816. Learned a little 68000 to play with Copper lists on the Amiga but never got very far with that. Tried to write a game on the Atari and got a nice playfield and some totally random sprites on a fine scrolled left to right screen but when it came to an AI for the sprites I just went blank. My maths was never that great, so AI was just not a thing I could get a grip on.

I know, learning 6502 when your maths is not great, does not compute, but I enjoyed the tinkering..

 

I'm just going to be a Coco 2 user with some upgraded and advanced hardware for a while. Because I am already learning 6502 Assembly with Mac/65 and relearning Atari Basic XE, which I already have the books and languages for from the great Atari community and my own assets. a

And thanks to great people and support in the Bally Astrocade community, who have been excited about my restoration and now upgrade into a PC, have given me great deals and gifts on upgrades, languages and books as well, so I think co-learning 6502 and Z80 assembly and Atari Basic& AstroBasic is enough for now.

Once I get on solid footing with those machines then I'll start learning 6809/6309 assembly and of course Coco Basic is just Microsoft Basic and adapting to it by then after learning other Basics will be easy. Plus, if I do any real programming of games or apps on the 6502 and Z80, there are a lot more machines it can be ported to than with the 6809. Of course any small changes needed for Dragon compatibility will be included in the original program.

Unfortunately, I have not had the same great experience attempting to get involved in the TRS-80 Coco or Dragon communities and so no social encouragement either, like with the other machine's communities. Basically only @Vyper68 here has become a fellow traveler in 6809 land with our largely compatible machines.

 

So now we both have CoCo’s we can compare notes better Matt. It was cheaper getting a 64K CoCo than trying to buy a Dragon 64 and with Two Tandy joysticks all the manuals and 6 cartridges it was a steal. When you look out there’s a lot more support for the CoCo than the Dragon but then again the CoCo had a lot longer lifespan so it’s not a surprise.
The 6847 in my PAL CoCo is a 6847T1 like Matt’s so it has a proper zero,asterisk and lower case characters and because the MC1372 is on the main board the the composite mod was very simple. I plan a S-Video mod to improve the picture further when the cable arrives.
So now I can have a look at OS-9 …