In a sketch I found the following instruction:

```
#define USB_CONFIG_POWER_MA(mA)                ((mA)/2)

```

And I want to be sure not to make any mistake: why are there two "mA"?

Which one should I replace by a value given that in a previous version of this code one just needed this line:

```
#define USB_CONFIG_POWER_MA(20)

```

to set the max to 20mA but now it gives a compilation error:

```
/home/henry/arduino-1.8.16/hardware/arduino/avr/cores/arduino/USBCore.h:99:29: error: "20" may not appear in macro parameter list

```

This seems to be the solution as it gives me no compilation error

#define USB\_CONFIG\_POWER\_MA(mA) ((40)/2)

but again i want to be sure!