Changes
/* Analog PC Joysticks */
The analog inputs are read from memory mapped ASIC registers:
6808h ADC0 Analogue Joystick 1, X-Axis (00h=Left=0 ohm, 3Fh=Right=180K 138K ohm) 6809h ADC1 Analogue Joystick 1, Y-Axis (00h=Up =0 ohm, 3Fh=Down =180K 138K ohm) 680Ah ADC2 Analogue Joystick 2, X-Axis (00h=Left=0 ohm, 3Fh=Right=180K 138K ohm) 680Bh ADC3 Analogue Joystick 2, Y-Axis (00h=Up =0 ohm, 3Fh=Down =180K 138K ohm)
680Ch ADC4 Unused, wired to +5V (twice the maximum of 2.5V) (returns 3Fh)
680Dh ADC5 Unused, wired to GND (equivalent to 0 ohm) (returns 00h)
680Fh ADC7 Unused, wired to GND (equivalent to 0 ohm) (returns 00h)
To read that registers: Unlock the ASIC, and then map its register to memory at 4000h..7FFFh.
Values measured by Octoate:
ADC input at 00h..01h = 0 Ohm (left/up)
ADC input at 1Fh..20h = 50 kOhm (center) (that is, the center of ADC values, not of the resistor values)
ADC input at 3Eh..3Fh = 138 kOhm (right/down)
== Analog CPC+ Joysticks ==
== Analog PC Joysticks ==
Analog PC Joysticks have a very similar 15pin connector. TheoreticallyBut with some differences, a few which cause compatibility problems. Statistically, many people reported the analog PC joysticks might be '''do work''' with analog CPC+ compatiblesoftware. However, in practice, this is rather unlikely Many other people reported it won't work - the potentiometers must have correct value, the button common pin must be correct, and the though it's quite possibly that they simply made some fundamental mistakes (like trying to use "digital" 15pin joysticks as "analog" joystick may not contain additional electronics like auto-fire circuits, electrolyte capacitors, or digital-switch to analog-signal convertersthat they didn't even had proper CPC+ software for testing).
* '''CautionButton Common Pin''' - compared with In PCs, the button-common-pin can be at Pin4 or Pin5, on the CPC+/GX4000 do output '''reversed polarity on the joysticks power supply''' pins, so it must be Pin4 (or Pin12 for 3rd-4th button; if any special electronics in '''PC joysticks may get destroyed''' when connecting them to a CPC Plus/GX4000). If necessary, rewire that pins.'''
== CPC+ Software with Analog Joystick Support ==
* [[FutureOS]] - (Plus version)* [[Tennis Cup 2 ( Cartridge )]] - allows to use Analog Joystick (as digital joystick replacement in two-player mode, see selectable in options menu- the game merely emulates digital inputs, it doesn't actually support analog input)
* RP11 Arnold V diagnostic ROM cartridge - allows to display the eight ADC inputs in numeric form
[[Category:HardwareCPC Plus]][[Category:PeripheralsFutureOS]][[Category:CPC PlusGames Programming]][[Category:StubInput Device]][[Category:Peripherals]]