Chris Atkins wrote:
>
> With the recent discussions on OSD chips and video, I wondered if
> anybody had a cheap solution for producing a mirrored video image.
> Normal TVs scan from left to right. I have a TV that is used in trucks
> as a backup monitor. It scans from right to left to give the driver the
> feeling he is looking in a mirror. I'd like to put some text on the screen
> with an OSD chip, but everything looks like the front of an ambulance ;-).
>
> Does anybody know of an OSD chip that has a user definable character
> set or can spit out the image in reverse?
>
> So far the best way I have come up with is to store the backwards text
> bitmap in some kind of memory and have a PIC or PLD spit it out a bit
> at a time (only need white letters). Then have a MUX switch between
> a white dot or the incoming picture. Timing can be generated by an
> Elantec EL4583 or something. Anybody know of an example circuit
> similar to this? (Besides the INK 32 weather station article). What is
> a good type of memory for this, VRAM?
>
> Any other suggestions are appreciated.
>
> Chris

NEC's uPD6453 has 16 user defined characters (RAM). This chip is
available, though I could never get clear if it's going to be
discontinued (like a lot of other NEC OSDs). Also, in Philips' 87C055
(83C055) you can define 60 characters (EPROM) in 18x14 format.
Best regards,

Gennady Palitsky
Jefferson Audio Video Systems
gennadyp@mainlink.net