New to retro-computing. - Page 1
Forum section: electronics / beginners

author: Byodood
author_rank: Newbie
timestamp: August 24, 2013, 03:31:29 pm
content: Hello eevbloggers! Total nub here! Today, I picked up my first retro computer set. 2 Radioshack TRS-80 Color Computers. I got them, plus 2 commodore floppy drives, for a whole dollar. And.... I don't know where to go from here. I don't have any tools or monitors to test them with so I've come here for help on what to do!Oh! I also got those books next to the computers. They are from the early 80's late 70's and tell you how to code in assembly!

author: AndrejaKo
author_rank: Frequent Contributor
timestamp: August 24, 2013, 03:56:33 pm
content: I don't want to sound rude, but the first step I'd recommend would be to post pictures on a forum in such way that they don't take up too much space. I already have 1920x1200 screen and I had to scroll quite a bit to even see what's on the image.Next, I'd recommend that you post in writing exactly what you have, preferably with a better description than just "books". This will allow people who do have experience in the field to more easily comment on what you have. Remember, you're asking for help, so you should make it as easy as possible for others to provide it.A step further would be to take clear, focused photographs of all the connectors the computers have and post them. You may even get lucky if you try Google's reverse image search. It may provide you with some names or keywords on how to look further. More experienced members may know directly what standards are used and might provide help. Remember that most of the picture are should show what you want to present to others. It's not easy to make a good photo, so try practicing. It helps!Also, remember Wikipedia! It can be a really good friend in such cases. I even found ROM dumps for a retro computer I was investigating few years ago on it.Finally, I wish you the best of luck with your retro-computing adventures!

author: dfmischler
author_rank: Frequent Contributor
timestamp: August 24, 2013, 04:04:25 pm
content: I remember laughing at one of my co-workers around 1983 'cause he wanted me to write software for him for that thing. He liked it though. I was busy writing PDP-11 code at the time (and I got rid of my last PDP-11 when I moved in 1999).Here are some links you might like.Glenside Color Computer Clubhttp://www.coco3.com/community/

author: mianchen
author_rank: Regular Contributor
timestamp: August 24, 2013, 05:08:44 pm
content: Quote from: AndrejaKo on August 24, 2013, 03:56:33 pmCtrl+scroll wheel is your best friend

author: FrankBuss
author_rank: Unknown
timestamp: August 24, 2013, 05:22:33 pm
content: Last month was the Retrochallenge competition. An interesting project was using a C compiler for the CoCo:http://retrotinker.blogspot.de/2013/07/rc-2013-sc-wrap-up.htmlI don't know much of this system, but from the Wikipedia article it looks like you can't use the 1541 or 1571 commodore disk drives for it which you scored, but you could buy a C64 for it

author: AndrejaKo
author_rank: Frequent Contributor
timestamp: August 24, 2013, 05:54:48 pm
content: Quote from: mianchen on August 24, 2013, 05:08:44 pmBut I do not want to change the zoom level so I can take a look at the picture which has too low information density! What's the point of a huge photo when at least 70% of the space on it is wasted (maybe I should say off-topic? we get a nice view of the background and tabletop, but not as nice of the computers, peripherals and books) and in addition to that, the extra resolution provides no additional information, since there are no visible details in the first place due to arrangement of objects of interest. That same picture would be just as good, if not better in say 480x270. It literally took me 15 seconds to find a site on the Google which does resizing, upload the image, resize it and download it back.If we, on the other had, had a picture of a densely populated circuit board on which we had to make out individual components and their connections, I wouldn't complain at all. In that case, scrolling would be welcome, since I'd be able to see in great detail small markings.Yes, I am on a crusade against photos of little use and I know this this reads a bit like

author: IanB
author_rank: Super Contributor
timestamp: August 24, 2013, 06:22:53 pm
content: With a TRS-80 you simply plug them in and switch them on.The snag is they may have a modulated UHF video output designed for a (retro) TV antenna input. You should look on the back and see what the connectors are. If you are lucky there may be a composite video output that you can plug into a suitable more modern TV or monitor.But apart from that, such computers were designed to be easy to use. If you switch them on and the display shows some start up text then you are ready to go. Just start using the keyboard and play.On the image thing, I do agree at a little thought here would help viewers. That image as loaded was 3196x1800, so it was probably right out of the camera at maximum resolution. Most cameras will allow you to select the image size before taking a picture, and 800x600 or so is good for most web purposes. Alternatively, I think imgur can also resize images for you.

author: Crazy Ape
author_rank: Regular Contributor
timestamp: August 24, 2013, 08:17:08 pm
content: Ian's post above is correct, you'll need either an OLD TV to use the RF (antenna) input............ or, the other option, is to build a small circuit for standard composite A/V output (TV RCA connection).The second schematic on this page looks like the best:http://www.tandycoco.com/composite.shtmlNote that the first schematic on the above page looks wrong (trimpot wiper), here is a corrected one:http://www.gimechip.com/files/CoCo/Frank_Gilliland/SKEMATIC.GIFHere's a very simple composite mod:http://www.retrocomputers.eu/wiki/index.php/Tandy_TRS-80_Color_Computer_%28CoCo%29_Composite_Video_Mod

author: Byodood
author_rank: Newbie
timestamp: August 24, 2013, 10:56:40 pm
content: Thanks for the info fellas. I'm sorry about posting big pictures but I wasn't sure if the thumb forum command worked here. I'm not home right now (out of town, left after I dropped the computers off at home :\) but I will post pictures of it all when i get back. Until then, I can pull some pictures from my phone for ya'll.The insides of the commodore drives look really clean and the ports and buttons on everything seem to work and look clean as well.Here is the cover of the books. Very retro.

author: Unknown
author_rank: Unknown
timestamp: August 24, 2013, 11:10:39 pm
content: Quote from: mianchen on August 24, 2013, 05:08:44 pmI started a post a while back suggesting a simple fix to the forum code to stop the large image thing, but no-one replied.

author: pickle9000
author_rank: Super Contributor
timestamp: August 24, 2013, 11:42:53 pm
content: I always thing of this thing when I think retro, although it's not at all. It is pretty cool cool though and looks like the guy did an excellent job.Maximitehttp://geoffg.net/maximite.html

author: GK
author_rank: Super Contributor
timestamp: August 25, 2013, 01:23:09 am
content: Funny. Just the other week I salvaged an old wooden desk that was getting ditched at work. Sanded it down, shortened it to fit in my study and reassembled with a few fresh coats of varnish. Used the extra bench space as an excuse to pull my old computers out of storage. There's a Acorn/BBC Model B, a Commodore 64 and an Amiga 600. The BBC blew a X-cap in the PSU shortly after powering it on (what a smokey stink!) but that is fixed now and is working fine. All those years ago I never new why I couldn't get the BBC composite video output to display in colour. Now I have the smarts to understand how the electronics side of thing works and the reason is clear - it's NTSC. I will have to make up an interface for the RGB video output to display on the Commodore 1084S monitor.The Commodore 64 works fine, with the exception of the F3/F4 key which I have to glue back on. The Amiga 600 has power supply issues that I still need to sort out (regulation drops out when the internal floppy drive spins up and increases the current draw).BTW, if you really want to get into programming on an ancient "personal" desktop computer, you really couldn't do much better that hunting down an old BBC, preferably the (much more common) model B. It has a huge array of ports/interfacing options and the best basic interpreter of its era (IMO). With very little programming knowledge you can get straight into stuff like drawing fancy high resolution graphics displays. The C64 with it peeks and pokes was a load of poo in comparison.I'm currently using my PC with its motherboard sound interface as the "tape" storage device, saving programs as *.wav files.

author: dfmischler
author_rank: Frequent Contributor
timestamp: August 25, 2013, 01:28:32 am
content: When I think retro-computing I think of aDEC KL10or maybe aCDC 6600. But I don't want one.

author: GK
author_rank: Super Contributor
timestamp: August 25, 2013, 01:33:06 am
content: I immediately think of a PDP-1 with that cool long-persistence, round CRT digital graphics display and I would love to own one. Not sure where I'd put it though.http://en.wikipedia.org/wiki/PDP-1

author: pickle9000
author_rank: Super Contributor
timestamp: August 25, 2013, 01:46:18 am
content: That DEC KL10 is awesome! Very 6 Million Dollar Man.

author: Shock
author_rank: Super Contributor
timestamp: August 25, 2013, 01:57:51 am
content: Google is the best place to start. Look up the specs of what type of video you could use on them, if you want to get them running that is.If you just want to open the boxes and take a look you have 4 there you can open up hehehe.

author: Byodood
author_rank: Newbie
timestamp: August 25, 2013, 02:59:28 am
content: Quote from: Shock on August 25, 2013, 01:57:51 amHmmm... I DO have 2 computers, and 2 drives... I could take one of each apart.I think I will ;3 give me a little bit.

author: FrankBuss
author_rank: Unknown
timestamp: August 25, 2013, 03:24:38 am
content: Quote from: GK on August 25, 2013, 01:23:09 amYou can use C for the C64 (and most other retro computers, too), then it looks like programming a modern microcontroller. And if you structure the code a bit, it is easy to read and to maintain, too:http://www.frank-buss.de/c64/sid-test.htmlBasic makes it more difficult to write good programs.

author: Byodood
author_rank: Newbie
timestamp: August 25, 2013, 03:40:26 am
content: Hang on to your butts, this is a big dump.- notice date code on bottom of case: 82.This is the inside of one of the floppy drivesEnjoy fellas

author: GK
author_rank: Super Contributor
timestamp: August 25, 2013, 04:38:30 am
content: Quote from: FrankBuss on August 25, 2013, 03:24:38 amWell sure, but for a "newbie" a good basic interpreter which makes it relatively easy to exploit the machines capabilities to some depth is a good start.-----------------------------------------------------------------------------------------------------------------------------BTW, these computers are not "retro", they are just old. Retro means something contemporary that is imitative of old design. For example the BMW Mini is "retro". The original Mini is just old.