forum speccy.pl
ZX Spectrum => HARDWARE => Wątek zaczęty przez: zaxon w 2014.05.16, 18:23:39
-
(http://images53.fotosik.pl/360/9e4cb142834d2439m.jpg) (http://www.fotosik.pl/showFullSize.php?id=9e4cb142834d2439)
-
A co to znaczy dla PROFI ?
-
To znaczy ze tylko z Profi dziala.
-
PROFI contain betadisk rom (tr-dos) then you need only FDD ports. But here is small problem:
FDD controller use ports #1F,#3F,#5F,#7F,#FF. All this ports are for writing and for reading.
Reading port #1F,#5F = collision with kempston joystick interface
Reading of port #FF - betadisk return values on bits D7 and D6, but this port is used in ZX software(games) as attribute port.
If FDD ports will always enabled, then may be problems with some zx games (screen synchro via port #FF) and will unusable kempston joystick.
FDD ports must be enabled only if tr-dos rom is connect. But this is not so easy detect...