Send Serial data through RS-232

[fatimamaz]

Hello,
I have pixels (12 bits each) and i need to send them serially by UART RS-232 while the maximum data bit is 9 bits. How can i send the data of each pixel without any compression?
Thanks

 

[KlausST]

Hi,

use two bytes per "pixel".

Klaus

 

[andre_luis]

There are lossy or lossless compression (which perhaps that's what you're referring to?), and if the update rate in the receiver side is a relevant item, you can consider some kind of variable allocation of data within the frame so that do not waste the most significant bits of the second byte if you were to send the 12 bits within 2 words of the UART.

 

[mjuneja]

Hello,
I have pixels (12 bits each) and i need to send them serially by UART RS-232 while the maximum data bit is 9 bits. How can i send the data of each pixel without any compression?
Thanks

What is maximum data bit means here??

Are you saying that out of 12 bits only 9 bits contains the actual data..

 

[fatimamaz]

12 bits are the actual data.

 

[mjuneja]

You can use 2 bytes/pixel as suggested by Klaus if transmit rate is not a challenge.

Otherwise you may try to fit 2 pixels (i.e. 24 bits) into 3 bytes as well. (if you want to save redundant bits)

like byte1 = pxl1(7 downto 0)
byte2 = pxl2(3 downto 0) & pxl1(11 downto 8) // concatenate lower 4 bits of pxl2 and higher 4 bits of pxl1 in a single byte
byte3 = pxl2(11 downto 4)