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.
Lots of resistors or some other DAC, as well as a microprocessor or microcontroller to program the 1143.
| # | Input | Output |
|---|---|---|
| 0 | CLK | SOUT0 |
| 1 | RST | SOUT1 |
| 2 | D0 | T0 |
| 3 | D1 | T1 |
| 4 | D2 | T2 |
| 5 | D3 | T3 |
| 6 | A0 | LED0 |
| 7 | WRT | LED1 |