Changes

'''The Plus''' and GX4000 cartridges access the Plus hardware improvements, but specific software can be created using the extra features without the need of cartridge hardware (contrary as it was claimed by Amstrad in 1991). The extra features are not locked by a hardware mechanism but only by a special 17 bytes-length sequence send to the CRTC. So, it's possible for everyone to create his/her own software on the Plus, using the extra features available through a 16kb [[ASIC]] I/O page. Except the extra-features, the 464 and 6128 Plus machines are almost fully compatible with the classic CPC generation. Some minor differences are noticeable in the components ([[8255|PPI]], [[CRTC]], [[Gate Array]][[Gate Array]]) contained in the ASIC and in the interrupt mechanism in vectorised mode.