Re: Was the UK that far ahead of US?
Oh and just out of curiosity, did anyone else feel Xmas 1984 was a bit of a let down after the joy of Xmas 1983?
The Dragon 32, arguably the best-known and most-successful of the UK's early 1980s home computer also-rans, was introduced 30 years ago this month. The micro's story goes back more than a year before its launch. Tony Clarke, a senior manager at Swansea-based toy company Mettoy - best known for its Corgi die-cast metal car …
My parents bought me a Dragon 64 for Christmas '84 because they were on fire sale in June since Dragon Data had closed, and I used that incessantly until I headed off for uni in '93 (and bought an Amiga A1200). I have fond memories of meeting the likes of CairanA (from above, plus Graham Kinns, Mike Stott, the PSE guys, and Stuart from the PD Library who unfortunately passed away) at the last few Osset shows in the early '90s, and still have my copy of the Dragon WIMP system - thanks for creating that Eddie! I remember writing a B-spline editor in that, and it was so slow doing the math in Basic!
If anyone from the North East Dragon Users Group (Chris, Fred, David, Les, John etc) reads this, I hope you are doing well!
I was the project leader for the Dragon 32 at PAT, or Patcentre as is was then known. I thought you might like to know what I remember of that time.
I remember spending a lot of time talking to a really helpful Motorola chip salesman called Robin Saxby. Yes, the same guy who later ran ARM and is now Sir Robin.
We certianly did not copy the CoCo. It was not really available in the UK because it had an NTSC video system which would not work on UK TVs in those days. The Motorola application for the SAM chip (synchronous address multiplxer) showed a complete home computer to which the CoCo was identical. We made numerous improvements to this app note. We included a real A/D and D/A convertors for generating the FSK signals used to store programs on tape. We added a parallel printer port and used the same chip to scan the keyboard. We had a separate power supply PCB which also contained the TV modulator. It was a single sided PCB so it saved cost but also allowed variants to different TV standards to be made cost effectively. We made a SECAM variant for France and also an RGB and US version.
I do not rmemeber Motorola suppying a BIOS. Microsoft wrote the Basic interpreter, which was essentially the same as the one they licensed to Tandy but with a few add-ons, but you were expected to create all your own peripheral drivers - a situation unchanged to this day. It was these drivers that Duncan (Smeed) wrote. I do not remeber the keyboard speed up being his alone. The nromal way to scan a key board is to activate a row and read the columns to see if a key has been pressed and repeat that for each row. Of course, most of the time there was no key pressed and this routine just wasted a lot of time getting a no key preessed result. We realised that becuase we had used the same chip to scan the keyboard as drive the parallel printer port, we could do one thing the CoCo could not, and that was activate all the rows at once. If you do this and then look at the columns, in one go you get to know if there are no keys pressed, the most common situation, and you can exit straight away. If you find a key has been pressed you scan as usual to find which one. This is what saved the time.
The PAL output had nothing to do with the CoCo. PAL was essntial for it to work on UK TVs. Few if any had SCART sockets so you had to create genuine PAL. Persuading a chip designed to make 525 line 60Hz NTSC to make 625 line 50Hz PAL instead is a non trivial exercise and needed a lot of descrete logic - ASICs were in their infancy then.
Two weeks before the official launch, the Spectrun 16K came out. The piggy back RAM PCB was designed, tested and ramped up for production in that two weeks. Later we used a bunch of Siemens 32K RAM chips that consisted of two 16K RAM chips literally piggy backed on eachother and later still upgraded the main PCB to 32K then 64K.
We then worked on the disk drive unit which was abandoned when Tony Clarke left and all development work went in house. What is probably not well known is that at the same time we were working on the successor to the Dragon, code named Draconis. This used a Motorola 68K processor and a very powerful graphics chip from NEC. Along with OS/9 as a true real time executive, this would have beaten the PC hands down as a business machine. But for the vagaries of the home computer market, we might all be using Dragons today.
Apologies if the bit about about the keyboard scanning in article came across as a software-only optimisation. You are correct in pointing out the Dragon 32 design used a different hardware setup for scanning the keyboard and this - in combination with the BIOS code - did result in a significant speedup in the BASIC interpreter. So, yes, your hardware design was the determining factor in this respect.
Thanks for filling in some of the background too.
Very long time no see. I tried to contact you about a year ago because I was contacted by someone who was doing a Dragon exhibit at the museum at Bletchley Park. He wanted an article on the Dragon from the developer's perspective.
Can you let me have your current email address?
It was myself (Simon Hardy) that you were in contact with - and in 2010 as part of the Vintage Computer Festival (GB) we managed to get a line up of a Dragon 32, Dragon 64, Three Dragon Professionals! and a Eurohard Dragon 200.
I run the website "World of Dragon" and wanted to try and get as much information from those involved in the Dragon recorded and archived.
I now volunteer as part of the Retro Computer Museum (https://www.facebook.com/RetroComputerMuseum or http://www.retrocomputermuseum.co.uk) where we hold regular public events and also open on request most Sundays.
Yes, it has been a very long time - I have many happy memories from those days. I have PM'ed (via LinkedIn) my current e-mail address.
Perhaps we should try and reorganise a reunion - The Dragon 32 at 32 perhaps!? - in 2014.
Sorry that I missed the Bletchley Park event...
Just wanted to say a massive thank you for the Dragon 32. It, without doubt, was the biggest reason I ended up working in IT. I spent hours and hours programming the thing and when I left school and into the wide world (as a YTS person) I was streets ahead of most of my peers and have been very well compensated for my work since.
once again thank you sir.
For a more in depth trip down memory lane - see http://www.retrocomputermuseum.co.uk and our facebook page https://www.facebook.com/RetroComputerMuseum.
We have public event on in Leicestershire, UK over the August bank holiday - come and see all of these systems and get hands on with coding, gaming or simply remembering the "good old days".
I was 5 when I was given this for Xmas (well me and my older sister but she never got a look in..) was truly great, some memoriable ones were Cuthbert series, Manic miner, Wizard Wars, ugg and ring of darkness
I was able to load some games and see the source code (basic) , by the age of 6 i was fiddling about with the text in games and typing out the games from Input magazine.... (possibly where my love of open source started..)
Was more reliable than any version of Windows...
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I was the one that ripped your games with perfect copies (not replicated tapes) and replaced your logo with the HyperSoft logo when the games were loading.
(this is from memory and is 29 yrs old so it maybe a little out!)
• write small program to load repeated text into memory from 1536 to highest memory point.
• load "whatevergameitwas", 1280 (this loaded them into higher memory and prevented the games from auto-running) (1536 was the start of high-res(!) graphics memory & games loaded at mem point 256)
• check memory dump to see where program load finished.
• change tape
• load "newlogo",2304 (this loaded my modified HyperSoft logo into what would be the "text buffer" - this was the logo that displayed whilst the game was loading)
• insert new tape
• save "name of game", 1536,<highmempointofprogramload,256 - Save code from mem point 1536 to high point and when loading execute at mem location 256 (allow auto-run)
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