All tone generators simply take the input clock frequency, multiplied by 256 and divide it by 16 times the generator’s divisor setting. It does this by using a ring oscillator to generate a faster internal clock to be able to generate a wider range of tones. Of course, the outputs are stil only updated as fast as the scan chain allows. The output is a 6-bit digital sample, but can easily be converted to an analog signal using a resistor chain. Also uses the leftover output pins as general-purpose outputs.
It is possible to use the DIP switches to program the generator according to the documentation. Writing 1101 into address 1, 1010 into address 2, 0000 into address 3 and finally 0001 into address 15 will cause a ~440Hz tone to appear on the output.