Second Fire button on the 2600...

Un viejo analisis de joysticks:

Additional Fire Buttons on the 2600:

                                   | Works | Reversed | Comment
                                   |       | Logic      |
===================|==================|===================================
Atari 7800 Pad   | no   |  x       | Both Buttons work the sameColeco controller  | no |  x       | Second Button has no functionality
SMS Control Pad | no    |  x       | Second Button has no functionality
SMS Control Stick  | no |  x       | Second Button has no functionality
SMS SG Commander   | yes   |  no          | NES-Style SMS controller²
Genesis 3-Button   | yes   |  no          | B = fire, C = smart bomb.
Genesis 6-Button   | yes   |  no          | B = fire, C = smart bomb.
Amiga CD32 Joypad  | yes   |  no          | red = fire, blue = smart bombOmega Booster Grip | (yes?)|  (yes?³) | To be tested????????????       | ?? |  ??     | To be tested°
² The Auto Fire Adjusting Slider for Button 1 seems to be broken on my
  SG Commader, but I think the test results are still valid.
³ Conclusion drawn both from reading the Thrust 1.2 source and from
  playing the Thrust 1.8 cartridge with the SG Commander, which is
  constantly thrusting when the button is _not_ pressed.
° I assume there's a lot more controllers to test, like several other
  Coleco controllers and various third party stuff.

Note: The version of Z26 I'm using (DOS 1.58) seems to have some weird
          implementation of the booster grip behavior: When one of the grip
          keys is pressed, the highest Bit of INPT0-3 gets set, but it
          doesn't get cleared when the key is released.

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