Atari ST series - Page 372

APPENDIX I
$19 Set Joystick Keycode Mode
T his co m m an d p u ts th e jo y stick p o rts in to k ey co d e m o d e . In th is m o d e,
th e IK B D sen d s cu rso r arro w k ey co d e s w h e n ev er jo ystick 0 is m o ve d from
th e ce n te r p o sitio n . T h e m ak e co d e is fo llo w ed im m e d iate ly b y th e b reak
co d e. T his m o d e h a s a v elo city fea tu re th a t allo w s y o u se n d th e k ey co de s
m u ch fa ste r if th e stick h as b ee n h eld in o n e d irection fo r lo n ge r th an th e
b re a k p oin t tim e d u ratio n . U n til th e b re ak p o in t is rea ch ed , th e k e y co d es re 
p e at a t a slo w e r r a te , b u t afte r th e b re ak p o in t is rea ch ed , th e y re p e a t a t a
faster ra te .
Input parameters
Byte
Number Description
1 R X : T h e le n gth o f tim e until th e h oriz on ta l v elo city b re ak p oin t
is re a ch ed , an d th e k ey rep e a ts b eco m e fa ster (in ten th s o f a
se co n d ). B y se ttin g th is to 0 , th e h oriz on tal v elocity fe atu re is
d isab led , an d V X is alw ay s u se d as th e tim e b etw e e n re p ea ts.
2 R Y : T h e len g th o f tim e until th e vertica l v elo city b reak po in t is
re ac h e d , a n d th e k ey re p ea ts b eco m e fa ster (in te n th s o f a
se co n d ). B y s ettin g th is to 0 , th e vertical ve lo city fe atu re is
d isab le d, a n d V Y is alw a ys u sed a s th e tim e b etw e en rep ea ts.
3 T X: T h e le n g th o f tim e b etw e en h o riz on tal k ey rep ea ts before
th e h o riz on tal b rea k p oin t is re a ch e d (in te n th s of a se co n d ).
4 T Y : T h e len gth o f tim e b etw e en vertical k ey rep ea ts b efo re th e
v ertical b re ak p oin t is re ach e d (in te n th s of a se co n d ).
3 V X : T h e le n g th o f tim e b etw ee n ho riz on ta l k ey re p ea ts afte r th e
h o riz on ta l b re ak p o in t is re ach e d (in te n th s of a seco n d ).
3 V X : T h e le n g th o f tim e b e tw e en vertica l k ey rep ea ts after th e
h o riz on ta l b re ak p o in t is rea ch ed (in te n th s o f a se co n d ).
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