sorry for update such an old thread.
Recently, I bought an HBI-V1 complete with box, manual and software.
It has been imported and adapted to PAL by LASP (an old Spanish MSX importer).
I have been studying the mod and I found following parts were changed or modified:
X101: PAL = 4.4333619 NTSC = 3.579545
R106: PAL = 4700 ohm NTSC = 1000 ohm
R107: PAL = 100 ohm NTSC = 1000 ohm
IC101 (V7020): Cut pins 19,20,21
There is no extra board also.
As far as I can see, there are no other parts modified.
My guess about CALL FMV is that allows to manually digitize fonts. As this cartridge is only a digitizer, not a superimposer, Sony seems to have imagined an alternative.
In stead of superimposing a text on a picture, you can add a text on a picture, by using a digitized font. Some parameters of CALL DFONT seem to allow the use of a specific built-in font (normal, bold, reverse, ?italic, ...), probably one of these parameters (?P for personal font) is for custom fonts created with CALL FMV.
Finally found what's the utiility of CALL FMD (not FMV as mentioned above!).....It makes different operations on the picture that is in the VRAM of the HBI-V1 cartridge and has 6 parameters. It seems to work like CALL AD, but with an interesting original second parameter:
CALL FMD (G,H,A,B,C,D)
H= Encoding type of image - 0 = YJK - 1=YJK + YAE - 2=RGB
So, regarding the information collected, the digitizer is able to get 6 bits per RGB component, so 18 bits but, there is no way get such 18 bits raw, as there is a converter chip in the middle ?
