* The following are not connected on GX4000 so the associated inputs are not defined (possibly high):
** Printer (data and strobe) ** Keyboard lines 0,1,2,4,5,7,8 ** FDC ** FDD motor ** Cassette read, write, motor ** The signals /ROMEN, ROMDIS, /RAMRD, RAMDIS, CRTC CURSOR, EXP, Printer BUSY
* When a system cartridge is inserted (this has been verified with a yellow and a green labelled system cartridge), the copyright message and a Ready prompt is displayed. If the fire buttons or directions are pressed on the first digital joystick you see X,Z and the arrows displayed, the same as if you had pressed these buttons on a 464/6128 Plus or CPC. Pressing Pause displays "P".
For details about the Plus/GX4000 hardware features, see [[Arnold V Specs Revised]].
== Booting your software from cartridge ==
Beware, the Z80 is in Interrupt Mode 0 by default. The FDC is in DMA mode by default. And the hardware sprites memory has random value.
Anyway, you have to initialize all internal components (Z80, PPI, CRTC, AY, etc) when you are booting from cartridge.
== Software ==