Print64

Library for printing 64-bit integers on Particle devices

The standard C library on Particle devices (at least as of Device OS 3.0) does not support 64-bit sprintf formatting such as %llu or %llx or Microsoft extensions like %I64u. This includes not only sprintf(), and its variations like snprintf(), but also things that use it, like Log.info().

API

toString (uint64_t)

Convert an unsigned 64-bit integer to a string

String toString(uint64_t value, unsigned char base = 10);

• value The value to convert (uint64_t)
• base The number base. Acceptable values are 2, 8, 10, and 16. Default is 10 (decimal).
• Returns A String object containing an ASCII representation of the value.

toString (int64_t)

Convert an signed 64-bit integer to a string (ASCII decimal signed integer)

String toString(int64_t value);

• value The value to convert (int64_t)
• Returns A String object containing an ASCII representation of the value (decimal)

Example

#include "Particle.h"

#include "Print64.h"

SYSTEM_THREAD(ENABLED);
SerialLogHandler logHandler;

void setup() {

}

void loop() {
    Log.info("millis=%s", toString(System.millis()).c_str());
    delay(1000);
}

The System.millis() function returns a uint64_t. It works like millis() but since it's 64-bit, it doesn't wrap around to 0 after 49 days so it's easier to do comparisons with it.

Note that you must add a .c_str() to the result of toString() when passing it as variable arguments to sprintf(), Log.info(), etc.!