Printf Question

[Greg]

This is probably a dumb question but I dont have as much experience with C as I'd like to Is it possible to printf a char as an ASCII character? printf_lib.c says %c is unsupported. But somehow strings enclosed in quotation marks print with no problems. How do I convert a byte to a single-character string?

[deltacoder1020]

Originally Posted by Greg

This is probably a dumb question but I dont have as much experience with C as I'd like to Is it possible to printf a char as an ASCII character? printf_lib.c says %c is unsupported. But somehow strings enclosed in quotation marks print with no problems. How do I convert a byte to a single-character string?

try creating a 1-element char array, and then assigning the value of the byte to the first element (element 0) in the array.

[Greg]

Unfortuately, this does not seem to work. I get some garbage as output and then the RC locks up. Could you post some example code?

And, actually, this is not really critical Its ok if I dont get it working.

[deltacoder1020]

Originally Posted by Greg

Unfortuately, this does not seem to work. I get some garbage as output and then the RC locks up. Could you post some example code?

And, actually, this is not really critical Its ok if I dont get it working.

last i looked, there were functions to output individual bytes and other things to the output window... try the PrintString() function defined in ifi_utilities.h/c

[Daniel]

If you read the file "printf_lib.c" (I think) you will see a comment that says "%c" is not supported. The best you are going to do is put the character into a char array two long setting your character in location 0 and '\0' (or zer0) in location 1, then print it using "%s" as the format and using the array name.

char t [2];
t [0] = 61; // Or what ever you character is.
t [1] = '\0' // Null character.
printf ("%s\n", t);

[deltacoder1020]

Originally Posted by Daniel

If you read the file "printf_lib.c" (I think) you will see a comment that says "%c" is not supported. The best you are going to do is put the character into a char array two long setting your character in location 0 and '\0' (or zer0) in location 1, then print it using "%s" as the format and using the array name.

char t [2];
t [0] = 61; // Or what ever you character is.
t [1] = '\0' // Null character.
printf ("%s\n", t);

yeah, try that... forgot about the null terminator, because i'm so used to just using strcpy gotten lax.

[Greg]

I actually figured this one out on my own last night Sorry forgot to post here.

[Ryan M.]

What was the fix, anyway? I like to know so that if I ever get it, I have an idea on what it might be.

[Greg]

Actually, the byte array thing worked on MS VC6.0 but didnt in MPLAB One way of sending an unsigned char as an ascii character is actually very simple. I just do what printf_lib.c does when sending a byte - assign the unsigned char to the transmit register (I think it is called TXREG) and then call WaitForTXEmpty.

[Ryan M.]

Originally Posted by Greg

Actually, the byte array thing worked on MS VC6.0 but didnt in MPLAB One way of sending an unsigned char as an ascii character is actually very simple. I just do what printf_lib.c does when sending a byte - assign the unsigned char to the transmit register (I think it is called TXREG) and then call WaitForTXEmpty.

Tricky. That interesting. Thanks for that info.