Null Modem Cable

The Null Modem cable had so few wires to attach, it was extremely simple to build, even for the novice. Because of this, and the quality of games with this feature, network gaming suddenly took off.

FrontEnd Lemming

One of the Lemmings Mike did to fill the Menu screen with.

Lemming Explosion

Dave based the Lemming's explosion on the one from the classic Williams arcade game: Defender

The Complete History of
DMA Design
By
Mike Dailly

Chapter 3
Part 4

Populous

Having a room at the front and back of the office, offered a cheat free environment, and Dave was eager to beat everyone. So, most days, you could now walk into the DMA office, and be faced with a long, thin, white cable running the full length of both rooms, while shouts would be coming from each direction.

Dave and Tony were master populous players, and would more or less annihilate anyone they played - usually Mike.

This didn't change much when playing stunt-car racer, and while Mike wasn't always beaten, he usually ended up falling off the track to rapturous jeering from the opposition.

With all this in mind, and with the new 2-player bug still fresh, Dave decided he wanted to try and get some link up code working. So, inside the shoot-em-up Mike was working on, he created a small function to control the mouse, and then pass the information needed down that little white wire to Dave's Amiga 2000.

Lemmings - 2 Player mode

While Dave controlled the Lemmings with his Mouse, Mike was controlling a second one, whizzing it around the screen via the null-modem cable.

Dave had somehow made contact with another Amiga programmer called Dave Whiteman, and he was given the task of finishing Mikes scrolling shoot-em-up, along with the entire source, and a general brief of "make a great shoot-em-up". So, once a week he would pop in to show his progress, and get further instructions and advice from the rest of the DMA team. 

Gary was now trying to get levels together for Cutiepoo, and had drawn the first in a series of test backgrounds. He, Tony and Dave then sat down to decide which style to use. The winner turner out to be the chocolate factory, since they could all see some funny situations cropping up in here.

As Mike was again without anything to do, Dave set him the task of building a funny front end screen for the new Lemmings game. The front end Dave had in mind was going to consist of hundreds of little lemmings, each animating differently from the rest, so that the whole screen was filled with them.

Some would then stop and pick up little white cards and spell out words - or that was the idea. Mike drew some animations of lemmings doing silly (and sometimes impossible) things, and then got them all jumping around on screen.

Cutipoo test background

This turned out to be a classic example of things sounding like a great idea, but simply not working. The screen was just too confusing, and the idea was dropped. Dave moved Mike onto the ST, and got him to start the ST version.

While Mike had coded some ST stuff before, he had never gotten that involved in it, so he called upon Wayne to help out in all the really tricky stuff. Wayne as usual, was only too happy to help, and Mike soon had all the hard stuff done.

Mike then went on to write a Blitter emulator, so that the Amiga Lemmings code could be ported without any real effort. This turned out to be great fun, and Mike enjoyed every second, so it wasn't long before he had a lemming walking around a real level.

Dave who was currently working on the editor, decided he needed some floppy disk routines so he could save levels out. Dave, again called on Brian to write this, and Brian soon had something up and running. But it wasn't to Dave's liking this time, so he decided to do it himself, and "DMA Dos" was born.

These turned out to be very simple disk loading and saving functions that could plug into any game, and were in fact used from this point on in all DMA games on the Amiga.

One of the times Brian was in visiting, Dave showed him the new Nuke function in Lemmings. To say he thought it funny would be an understatement, since he almost fell backwards off his seat laughing!

DMA were even offered a spot on the T.V!

The year was marching on, and it was now May. Mike had just turned 20, and the second ITV Telethon was about to begin. DMA decided to try and write a sponsored game, from scratch - in a day!

This needed the whole workforce. Russell, Dave, Mike, Steve and Gary and Scott all started on Monday 28th May to write "Super Off-Road Hot Turbo Buggy Simulator"

It was basically a simultaneous 4 player SuperSprint style for the Amiga. Russell did the physics; Dave did the drawing, OS etc. Mike did input and front-end, while Steve did the music. Needless to say, Scott and Gary did all the graphics.

 It was a long day for the DMA team, from 9:30am to past midnight; but it got done, and was actually fairly good fun. It must also have been one of the first 4 player games around, but only friends and family ever saw it. They struggled towards the end, and the Music Steve did, ended up being dropped due to lack of space.

Null Modem Cable

The null modem cable is a serial cable. Serial cables send information one bit at a time. A bit is the smallest piece of data you can store on a computer, it can either be a 0 or a 1. Games would usually stream the joystick and mouse information the wire so that the other machine can "play" both players. A joystick would usually consist of 5 bits. Up,Down, Left, Right and Fire. 1 for yes, 0 for no. So when you press UP, it would send a 1 for up, and so on.

Amiga 3000

The "Blitter" was part of the Amiga's Agnus chip, and allowed for fast printing of graphics and sprites. The Atari ST didnt have a chip like this, and the CPU had to do all the work.