Readme update

README.md

@@ -26,6 +26,8 @@ We will not use any LED driver IC. We will either simply use constant voltage, o
 
 ## Notes
 
+### Build
+
 In fw folder run:
 
 ```
@@ -33,3 +35,24 @@ cmake -DCMAKE_TOOLCHAIN_FILE=cmake/gcc-arm-none-eabi.cmake   -S ./ -B Debug -DCM
 arm-none-eabi-objcopy -S -O binary led_driver.elf led_driver.bin
 st-flash write led_driver.bin  0x8000000
 ```
+
+### Debug
+
+```
+target extended-remote localhost:4500
+gdb led_driver.elf
+# in gdb then:
+load
+```
+
+
+### Design notes
+
+- bez zateze (bez zapnutych tranzistoru u H mustku) je samovybijeni cca 0.7 V za 50 ms (v prvni chvili, z 5V na 4.3V)
+    - coz odpovida cca tomu ze tam je zatez (2k || 2k) ohm = 1k ohm, takze casova konstanta RC je 0.3 s, takze na 80% (4V) by se to melo dostat za 0.2 RC = 0.2 * 0.3 s = 0.06 s = 60 ms, coz zhruba sedi
+    - viz [zaznam se Saleae](./data/vybijeni_C_50_ms_strida.sal)
+    - coz zhruba sedi s vypoctem:
+        - $Q_{partial} = Q * dV / V_0 = V_0 * C * dV / V_0 = C * dV = 330e-6 * 0.7 F = 0.00023 F$
+        - I je zhruba 5 mA (5V, 1k zhruba hodnota delice (viz nahore))
+        - Q_{partial} / I = 0.046 s = 46 ms, coz zhruba sedi tem 50 ms ktere jsem nameril
+    - TODO zvysit rezistory napetoveho delice, 1k je malo