LSP 1st

BIOSF_CLEARSPR ($C004C8): Clear sprites
Warning: register contents aren't preserved ! (Uses D0, D1, and A0)


 * All maps are cleared with tile # $FF, no special attributes (all SCB1 to $00FF,$0000)
 * All shrinking values are set to max (all SCB2 to $0FFF)
 * All heights cleared to 0 (all SCB3 to $0000)
 * All X positions are set to 380 (all SCB4 to $BE00)