Finalement, comme ca peut etre utile pour d'autres personnes, je vais ecrire ca en anglais. Desole aux french-only ;)
Okay, so I've got some CDM102 that i scavenged from od Baystack Network hubs (10-BaseT, if that ain't old :p). The CDM102 is a 12×5 bicolor (green/orange) LED matrix. You should be able to light individually each of the leds of the matrix. The CDM102 has got a 6-pin interface with the pinout below:
The matrix refresh rate appears to be 40Hz
Pixel datagram: 9 clock cycles, (started by high PXLJMP edge ?). 1pixel:115uS → 115uS * (12×5) = 1/40Hz
Okay, that sould work. So one pixel datagram should carry the color.