Audio with PWM

It is possible to generate sound with the APFxxx boards without any sound chip, just by using the PWM output and the i.MX possibilities:

Quality

Sound quality produced is low (8bits @ 8, 16 or 32KHz) but very sufficient to reproduce voice or small sounds. PWM activation/deactivation is generating "clac" each time you play a sound (for the moment) but using some electronic filters or playing "blank noise" could solve the problem.

Linux driver

• Armadeus PWM driver

Links

• http://www.fpga4fun.com/PWM_DAC.html FPGA PWM IP