printf outputs wrong result when do multiplication

volatile unsigned char a; a = 3; printf("%u\n", a * 100); The output is 11264. Why? Any reply would be greatly appreciated.
Why output data is wrong by serial?

hello,everyone! I wrote a program about serial communication and when I run it on simulator,it is no problem, but when I upload it to the Phytec KitCon167's flash,something wrong occur. The program...
CMSIS-DSP: CFFT with Q15, wrong output

Hi, I changed the CMSIS-DSP frequency bin example to Q15 format (or at least I'm trying to do so), but I'm getting wrong results. My changed code: /* =================================================...
CMSIS-DSP: CFFT with Q15, wrong output

Hi, I changed the CMSIS-DSP frequency bin example to Q15 format (or at least I'm trying to do so), but I'm getting wrong results. My changed code: /* =================================================...
Why output data is wrong by serial?

hello,everyone! I wrote a program about serial communication and when I run it on simulator,it is no problem, but when I upload it to the Phytec KitCon167's flash,something wrong occur. The program...