Re: [avr-chat] Printf with leading zeros?

[Rick Mann]

On Feb 1, 2011, at 05:49:10, Michael N. Moran wrote:

> On 02/01/2011 04:19 AM, Rick Mann wrote:
>> I'm trying to output a byte as a hex value with zero padding. I do something 
>> like this:
>> 
>>      uint8_t val = 4;
>>      int len = snprintf((char*) sBuf, 64, "%02x\r\n", val);
> 
> I use this format "%2.2x" to get the behaviour you desire.

I tried that, and it had no effect. Moreover, it shouldn't be necessary.

I noticed that switching to the floating point version of the library improved 
things, but didn't fix them altogether. For example, I added some logging to my 
code that uses "%#02x". This is supposed to produce strings that look like:

        0x00
        0x01
        0xff
        etc

But the actual output depends on the value. If

        Hex value       Output
        ---------       ------
        0x00            00
        0x01            0x1
        0x06            0x6
        0xb0            0xb0
        0x69            0x69

There is clearly something broken in the library.

-- 
Rick