Online Hex to Text Decoder

I have a program that reads in hex strings, and returns text based on the parameters of the string. A hex string goes as follows:

A : B : C

A - Length of B

B - Name of interface

C - Unimportant

so for example;

0465746830010000 = 04 : 65746830 : 010000 =4 : eth0 : __________

Now, I want to process the hex strings so that if there is a character that isn't in the alphabet, 0-9, or '-' , it lets me know somehow.

Such as here :

026601000002 : 6601 : _______2 : f[unreadable] : _______

Any ideas on how would I process this so that it lets me know if any of the characters outside of these parameters arise?

I'm trying to get random hex value between range of hexes:

random.randint(0xfff000, 0xffffff)

I got the range limits from JSON, as a string.

{"range": "0xfff000,0xffffff"}

How can I convert these strings(after splitting) to hexadecimal values?

I have code as below:

x = readsomevalue();print x

The printed value is an integer. I want this to be printed in hexadecimal. Any standard methods to do that?

I use the php_serial.class.php and have one question. When I send this below line to my device everything runs fine.

$serial->sendMessage("\x02\x06\xf1");

But when I do this way, nothing happens.

$str = "\x02\x06\xf1";$serial->sendMessage($str);

Anybody has any idea as why this is happening?

I'm trying to read hex values from a binary file. I don't have a problem with extracting a string and converting letters to hex values, but how can I do that with control characters and other non-printable characters? Is there a way of reading the string directly in hex values without the need of converting it?