I am trying to handle a 7 byte Desfire card UID. Things have been fine using a uint32_t variable to hold and display the 4 byte MiFare card UID. I thought I would use uint64_t instead of uint32_t - unfortunately snprintf() does not appear to handle C format conversion specifier %llu - output is “l…

It’s a documented limitation . As a workaround you can use the Print64 firmware library in the community libraries. The source and instructions can be found in Github .

Snprintf() not handling %lli or %llu for int64_t and uint64_t respectively

Firmware

ScruffR December 30, 2020, 1:26pm 2

I guess this statement from 2016 is still valid

Topic		Replies	Views
How can I print a uint32_t {aka long unsigned int} with snprintf? Firmware	5	9422	August 30, 2017
Weirdness with sprintf Firmware	2	991	June 4, 2015
Dealing with 40 bits Libraries	18	702	April 15, 2022
Issues with converting float to string with sprintf Troubleshooting	77	31754	September 14, 2015
Snprintf mixed types - FIXED General	11	2222	September 15, 2016

Snprintf() not handling %lli or %llu for int64_t and uint64_t respectively

Related topics