23-12-2012, 01:38 PM
The +2s and +3s were the first Specs under the Amstrad label. They had everything that Sinclair should have included with the first issue computers back in 1982. To be fair to Sinclair, they were trying to produce a computer for the masses, for a fixed price. Unfortunately for Amstrad it was a case of too late for the market as buyers were going towards the PC market.
Now decently loaded the +3 in this example sports a dedicated external FDD port, centronics, RS232, RGB / Aux, two joystick ports and best of all a proper reset button. Sound on this board is the bog standard AY-3 series chip. On the mainboard photo the two ROMs (one for Sinclair 48k and the other for Ams 128k mode) can be seen next to the Z80 processor. A big failing on this machine, although marketed as a 128k machine you could not fully utilise it for programs unless you used machine code for bank switching. Instead the memory was made available as an internal volatile drive called M:, whose contents were lost when you powered down.
Another failing, AMS decided to use their 3" stiffies rather than the usual more common 3.5" floppies a la PC fame. The first time I owned a +3 I did manage to interface a 3.5" drive to the rear port and that made life a lot easier as the price of AMS 3" stiffies were pretty prohibitive. There are mods on the internet to fit proper 3.5" drives.
One other note, for those who really want to go the full hog. Doing a search for storage options for Zx Spectrums revealed several circuit boards to interface IDE drives via the expansion port. There is a basic 8 bit design that does not utilise the whole drive due to address port issues but one project uses a GAL to convert the 8 bit output from the Spec to the 16 bit control the IDE drive requires. Asounding stuff, beats a microdrive hands down for speed of access and storage capacity.
Now decently loaded the +3 in this example sports a dedicated external FDD port, centronics, RS232, RGB / Aux, two joystick ports and best of all a proper reset button. Sound on this board is the bog standard AY-3 series chip. On the mainboard photo the two ROMs (one for Sinclair 48k and the other for Ams 128k mode) can be seen next to the Z80 processor. A big failing on this machine, although marketed as a 128k machine you could not fully utilise it for programs unless you used machine code for bank switching. Instead the memory was made available as an internal volatile drive called M:, whose contents were lost when you powered down.
Another failing, AMS decided to use their 3" stiffies rather than the usual more common 3.5" floppies a la PC fame. The first time I owned a +3 I did manage to interface a 3.5" drive to the rear port and that made life a lot easier as the price of AMS 3" stiffies were pretty prohibitive. There are mods on the internet to fit proper 3.5" drives.
One other note, for those who really want to go the full hog. Doing a search for storage options for Zx Spectrums revealed several circuit boards to interface IDE drives via the expansion port. There is a basic 8 bit design that does not utilise the whole drive due to address port issues but one project uses a GAL to convert the 8 bit output from the Spec to the 16 bit control the IDE drive requires. Asounding stuff, beats a microdrive hands down for speed of access and storage capacity.
