Mise à jour de 'README.md'

README.md

@@ -26,11 +26,13 @@ pip install pysstv
 ## Specs to do
 ### Get the default shell
 
-Should have a Serial interface on GPIO14(UART0_TXD) and GPIO15(UART0_RXD).
-I'm using a cheat FTDI232, from anywhere.
+Should have a Serial interface on **GPIO14**(UART0_TXD) and **GPIO15**(UART0_RXD).
+I'm using a cheap FTDI232, from anywhere.
 
 ### Enable secondary UART port
 
+/!\ This step don't works, should not use it ! /!\
+
 Should add this config parameters to `/boot/config.txt` :
 ```
 dtoverlay=disable-bt
@@ -38,8 +40,19 @@ dtoverlay=uart1,txd1_pin=32,rxd1_pin=33
 force_turbo=1
 enable_uart=1
 ```
+Now we ~~can~~ use **GPIO12** and **GPIO13** for a secondary serial port
+
+### Switch the output soundcard to GPIOs
+
+We have to play WAV files from the PySSTV converter, and put it directly in the microphone +/- input of the SA828 radio module.
+
+By the way, we don't need stereo output, that's why I only made a single RC filter for filtering frequencies over 20Khz.
 
-Now we can use GPIO12 and GPIO13 for a secondary serial port
+The configuration of `/boot/config.txt` will contain this line, then you can connect **GPIO12** and **GPIO13** to a stereo jack.
+
+```
+dtoverlay=audremap,pins_12_13 # for pins 12 and 13
+```
 
 ## Usages