Download ColecoVision Coding Guide

DECODER
ADDRESS : 1F79
INPUT:
H = Controller number (0 for player #1, 1 for player #2)
L = Segment number (0 for fire+joystick, 1 for arm+keyboard)
FUNCTION(S):
If L = segment number 0
- Load spinner counter SPIN_SW0_CT or SPIN_SW1_CT in E
-
Call CONT_READ
-
Load joystick data in L (A AND 0F)
- Load Fire state in H (A AND 40)
Else L = segment number 1
-
Call CONT_READ
-
Load decoded key value in L (0 = key 0,… , 9 = key 9, A = key *, B = key #, F = no key)
-
Load Arm state in H (A AND 40)
OUTPUT:
H = State of Fire (if segment number = 0), Arm (if segment number = 1)
L = State of Joystick (if segment number = 0), Keyboard (if segment number = 1)
E = Spinner (if segment number = 0)
CALLS:
None
CALLED BY:
Under user program control.
NOTES:
Destroys All
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