Hi Ronny
Some things I have learnt (you may know already but it may help).
To be sure I wired in my reset (took a bloody long time to find that little trick - grrr!!). If you dont have it, try powering on and off - sometimes its ok, sometimes it not (on mine anyhow).
I guess you give the camera plenty of ‘sync tries’ - I found it needs about 20 to 30.
The camera draws 45mA after it has sync’ed but if you dont talk quickly, it will go into sleep mode and needs another sync cycle.
I have found downloading at 115Kb works ok from a PIC 18F458.
Wierd … you get no reply data at all?
rgds
mb