need Advise on parameter in this function , u8g2_u8toa( (uint8_t)(fps/10), 3)

I'm looking thru an example in arduino IDE regarding >> Frames Per Second: Display Performance Test. Trying to understand it.

strcpy(buf, u8g2_u8toa( (uint8_t)(fps/10), 3)); i've attached the sketch, it at line 511.

what does the '3' in the src argument means? which part of the u8g2 library can i go to for more info about this, u8g2_u8toa( (uint8_t)(fps/10), 3)

Can anyone advise me. Thanks.

FS.txt (37.3 KB)

For Newbie,

read >> http://www.cplusplus.com/reference/cstdlib/itoa/