Knight Lore: Routine at 53367

53367: Read Kempston Joystick

Used by the routine at ReadControls.

Reads the controls from a Kempston joystick.

Output
C	The controls

Set each control bit from the Kempston port.

ReadKempstonJoystick

53367

IN A,(31)

Read the joystick.

53369

LD C,0

Set the controls to none.

53371

BIT 0,A

Set the right control if the joystick is pushed right.

53373

JR Z,ReadKempstonJoystick_TestLeft

53375

SET 1,C

ReadKempstonJoystick_TestLeft

53377

BIT 1,A

Set the left control if the joystick is pushed left.

53379

JR Z,ReadKempstonJoystick_TestDown

53381

SET 0,C

ReadKempstonJoystick_TestDown

53383

BIT 2,A

Set the pick up control if the joystick is pushed down.

53385

JR Z,ReadKempstonJoystick_TestUp

53387

SET 4,C

ReadKempstonJoystick_TestUp

53389

BIT 3,A

Set the walk control if the joystick is pushed up.

53391

JR Z,ReadKempstonJoystick_TestFire

53393

SET 2,C

ReadKempstonJoystick_TestFire

53395

BIT 4,A

Set the jump control if the fire button is pressed.

53397

JR Z,ReadKempstonJoystick_Done

53399

SET 3,C

ReadKempstonJoystick_Done

53401

JP ReadControls_Finish

Jump to ReadControls_Finish.

View the equivalent code in;