A82: Port 1, the keyboard port.
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A82: Port 1, the keyboard port.
Tell me if this routine for checking the keyboard port is correct.
ld a, %01111100 ; masks out all keys except
out (1), a ;ENTER + - * / ^ CLEAR UP DOWN LEFT RIGHT
in a, (1) ;Returns the bits read from the keypad
push AF ;af saved in stack
bit 6, a ;load bit 6 of a into a
jr nz, quit ; if a is 1 the key pressed is clear, jump to quit
pop AF ;reload AF from the stack
push AF ;store AF back into the stack
bit 2, a ;load bit 2 of a into a
jr nz, move_right ; if a is 1 the key pressed is right, jump to move right
pop AF ;reload AF from the stack
bit 1, a ; load bit 1 of a into a
jr nz, move_left ; if a is 1 the key pressed is left, jump to move left
I got the keypad port information from 82ports.txt.
BTW thanks for the display port routine Dines. What does RCL L do?
How much faster is writing 16 bits directly to the display port rather than
using
Dines's point_on and point_off
PLEASE tell me of any mistakes that I might have made in the code.
Thanx
Gerad
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