follow up :
i've just had 'limited' success in driving the ILX551A ,
very little change programming change from the other chip (upd3799cy)
& i save myself two pins
no data collection as yet but i can see the output change on the scope
whoo hooo !!
it requires VERY little light (i'm up to 200lines per sec ) & still get resonable responce in a medium dark room on a cloudy day ...
& it appears as the native output is close to max 3.5 volts -- so if i clamp it i may beable to feed the arduino direcly (probably have to buffer it but makes life easier ..... )
have to wait till monday to get sockets , clamping diodes , & assorted other things ...