RGB2HDMI Q&A

	A	B	C
1	Field	Question	Answer
2	Connectors	Does the HDMI connection power	No, even though HDMI allows powering external devices, this board does not for the sake of safety
3	Capture	I see noises on the image that cannot be seen on the CRT, what can it be?	Can be 3 things 1. The converter has no bandwith limitation, so noises of upper frequencies might overlap in lesser frequencies. An external bw limitation can be done for each specific computer 2. Related to the above, aliasing, if the sampling rate is lesser than the origin image rate, artifacts might appear. lesser resolutions are used to manage more colors due to memory limitations 3. HSYNC interrupt response time and code jitter: the firmware is not yet perfect but perfectible. So the code might be slow or non deterministic to manage a line. Will improve
4	Capture	On Amiga 1200 I see the screen greenish with lower brightness	Some Amigas as the 1200 includes SOG (Sync on green) that rises the level of green as the new DC level and lowers it for vertical and horizontal sync. A specific branch is being worked to detect SOG at least to remove the green component and correct the color balance Future on screen configuration might add color balance. Also is possible to filter SOG using 220uF caps to separate the offset. (one per color)
5	Capture	The screen goes black if the device is powered and has currently video signal	There is a known race condition that if you power the system and there is RGB video, the HDMI does not start, will be fixed, but for the time being, just hit reset button
6	Display	Is it possible to have other resolution modes besides 640x480p?	Yes, the dvi library allows other resolutions and future work can include those modes. Since RGB computers are near to 640x480 resolutions it is better this mode to fit the RGB frame without image manipulation Currently different capture modes or resolutions means different compiled firmware, for sake of simplicity we have 320x240@16 bits and 640x40@8 bits
7	Display	My HDMI screen does not work	The current mode of work is DVI, which is the precursor of HDMI, some display might not accept it. Future work to support HDMI1.4 is on the work, this will add also audio
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