[avr-gcc-list] Problems with float numbers

[Jose Javier Segura Juarez]

Dear AVR programmers community. This is the first time i write to this mail
list.
I am trying to generate a pulse with modulation with the timer1 of the
ATmega128.
The problem resides when i try to do an operation like

uint16_t
uint8_t percent=50;
char buff[17];

OCR1AH = (0x400 * percent / 100) >> 8;
OCR1AL = (0x400 * percent / 100);
sprintf(buff, "PWM: %d %f", percent, 1.0);
lcd->String(buff);

lcd is a pointer to an object controlling a 2x16 character lcd.
The problem is that lcd prints ? instead 1.0. The rest of text is printed well.
I linked math and printf_flt librabries but the problem persist.
I think the problem resides in the float treatment by sprintf.
I want to make a motor control application.

Can somebody help me?
Thanks

Jose Segura
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