Dragon ‘poke’runs into problems

DRAGON software houses selling programs which use the so-called ’speed-up Poke’ are running into problems of software incompatibility.

In earlier versions of the Dragon 32, the command Poke 65495,0 (Hex: HFFD7,0) can be used to increase the operating speed of the Dragon’s 6809E processor. A number of software houses have taken advantage of this fact to make their games run faster.

The problem is that around 20 percent of Dragons now being produced will not accept the speed-up Poke command and therefore the games will not run. Among the programs affected are Beyond Software’s Up Periscope and CTech’s Flight Simulation.

The Dragon’s 6809E processor is rated at a maximum operating clock speed of 1MHz and runs in normal use at 0.98MHz. The speed-up Poke increases the clock rate to 1.8MHz. It then depends on the tolerance of individual chips whether a particular machine will accept the Poke command.

One company which has found a solution to the problem is Microdeal. Its programs offer a menu choice at the start of each game where the Dragon owner can ‘choose to play a version either with or without the speed-up Poke, depending on whether or not the Dragon concerned will accept it.

Dragon’s Cathy Hyde says: “We do not recommend that Dragon users use the Poke because we cannot tell what long-term harm it will cause the machine. It is not just the Dragon’s processor which has been designed to run at 1MHz, but the whole design of the computer. The peripheral interface adaptor which communicates with the keyboard and parts of the Ram have also been designed to work best at less than 1MHz.”