08-04-2024, 04:27 PM
The next steps in the development cycle are all about Video and Sound outputs.
My intention is to do away with the old composite and RGB video outputs (Gasp!).
It's getting tricky these days to find suitable monitors / video output solutions to see
a Microbee's output with good quality. While there are still plenty of TV's around that
will accept the standard monochrome composite video output from the bee,
colour output usually means finding an upscaler or a device with a Scart input and
making up suitable cables / interface circuitry.
I just don't want people to have to buy something else to get a decent picture out of
their new kit.
Proper HDMI output is now what I've decided to implement. It makes it simple to get
decent quality video out, and no problem with finding a suitable display to run it on.
I've designed a small development board [above] for the parts I want to use that will go onto
the FPGA board in place of the RGB output section. The PCB has been ordered today.
If you have a look at the board, it also has an I2S DAC for the sound and line level stereo output.
The I2S bus also connects to the HDMI transmitter, so you will be able to have sound output
from your chosen display as well (assuming it has speakers) via the HDMI cable.
I'll be upscaling the Microbee's video within the FPGA to either 640 x 480 or 1280 x 960.
I will wait and see the results of the upscaling on both resolutions before committing to one.
As well as supporting the Microbee's normal bit bashed (via the PIO) sound, I'll be implementing
8 bit dual channel (stereo) sound FIFO's. The bit bashed sound will be summed into the stereo
audio as well.
I'm very much looking forward to getting these 2 important parts implemented.
Stay tuned.
My intention is to do away with the old composite and RGB video outputs (Gasp!).
It's getting tricky these days to find suitable monitors / video output solutions to see
a Microbee's output with good quality. While there are still plenty of TV's around that
will accept the standard monochrome composite video output from the bee,
colour output usually means finding an upscaler or a device with a Scart input and
making up suitable cables / interface circuitry.
I just don't want people to have to buy something else to get a decent picture out of
their new kit.
Proper HDMI output is now what I've decided to implement. It makes it simple to get
decent quality video out, and no problem with finding a suitable display to run it on.
I've designed a small development board [above] for the parts I want to use that will go onto
the FPGA board in place of the RGB output section. The PCB has been ordered today.
If you have a look at the board, it also has an I2S DAC for the sound and line level stereo output.
The I2S bus also connects to the HDMI transmitter, so you will be able to have sound output
from your chosen display as well (assuming it has speakers) via the HDMI cable.
I'll be upscaling the Microbee's video within the FPGA to either 640 x 480 or 1280 x 960.
I will wait and see the results of the upscaling on both resolutions before committing to one.
As well as supporting the Microbee's normal bit bashed (via the PIO) sound, I'll be implementing
8 bit dual channel (stereo) sound FIFO's. The bit bashed sound will be summed into the stereo
audio as well.
I'm very much looking forward to getting these 2 important parts implemented.
Stay tuned.