ElectrEm is an emulator of the Acorn Electron, an 8bit microcomputer first launched in 1983 that was once the fourth best selling in the UK market. Although sold as compatible with the BBC Micro, the only shared component is the 6502 CPU.
All other compatibility is achieved through a well documented firmware interface to graphics mode setting, sound generation and keyboard/joystick input.
Although the number of programs that directly use the Electron hardware so as to be incompatible with the BBC is small, the Electron is subject to a variable bus speed that makes most Electron software work at the wrong speed on the BBC and makes the implementation of an emulation based on an existing BBC emulator or almost any other 6502 emulation code impractical if not impossible.
ElectrEm also strives for ease of use to an extent not previously common in the Acorn emulation community. It is enough to point ElectrEm towards a tape or disc image and it will automatically configure the emulated hardware so it will become a compatible form while launching it.
What`s New in This Release: [ read full changelog ]
· sound: fixed an overflow problem that sometimes meant for quite inaccurate sound, Arcadians being a prime example
· boring interrupt stuff: on a tip from Tom Walker, I effected changes in the generation of interrupts while the counter is in tape output mode. Result? Evening Star and Southern Bell now work -- sound and everything!
· moving towards a ROM paging fix per the observations of John Kortink on the Stairway to Hell forums
· there is now the option of running the emulator with a persistent state (i.e. when you start ElectrEm, it puts itself into the same state it was in when you last closed it), though presently it forgets what media you were using
· added a Tape entry on the menubar, analogous to the existing disc entry
· some fast tape loading fixes -- better than before, still imperfect
· fixed bug where if the emulator encountered an opcode that would halt a real Electron forever or one it doesn`t understand (which shouldn`t really happen anyway), it displays endless warnings to...
