Printing Hex into Serial Port

Using Arduino Programming Questions
1

Hello! Can someone please help me identify where I am going wrong in this code. I am trying to print out the hexidecimal value exactly as it is shown.

char msgString[128];

void setup() {
  // put your setup code here, to run once:
  Serial.begin(9600);
  Serial.println("<Arduino is ready>");
}

void loop() {
  // put your main code here, to run repeatedly:
  uint64_t receivedMsg = 0x1000000100000000;
  sprintf(msgString, "Incoming message: 0x%.16llX",receivedMsg);
  Serial.println(msgString);
  delay(1000);
}
2

looks correct for me:

Incoming message: 0x1000000100000000

what do you expect instead?

3

What do you see in the Serial Monitor after the execution of: Serial.println(msgString)?

4

That's exactly what I expect, however I only see
Incoming message: 0x

5

Incoming message: 0x

6

it works on a 32bit microcontroller like the ESP32.
On which microcontroller are you testing?

8

I am testing using Arduino UNO

9

do you need it in a buffer (which is later used to be printed) or do you want to get it printed on Serial i first place only?

this post will give you some ideas for both ways:

10

I am mainly printing it for verification purposes at the moment. I just want some way of seeing if I am correctly doing bitwise operations and things like that. It's for a larger project and I'm struggling with some of the basics. Thanks for linking that post though, I will go check it out

11

UNO does not know how to print uint64_t

careful as well if you use Arduino's bit manipulation macros as some are tailored for 32 bits max

(see the UL and not ull)

12

Why not sprintf(msgString, "Incoming message: 0x%.16X",receivedMsg); ?

without the 11 between 16 and X

13

because that would be for an unsigned integer (in hexadecimal format) and not a unsigned long long

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14

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