The sine wave sequencer state machine selects one of the four sine waves to be driven onto the sine signal at the top-level of the design. The state machine has one input and one output. The following figure shows the schematic elements of the state machine. Refer to this diagram as you read the following description and as you perform the steps to view and repair the state machine glitch.
- The input is a scalar signal called “button”. When the button input equals “1”, the state machine advances from one state to the next.
- The output is a 2-bit signal vector called “Y”, and it indicates which of the four sine wave generators is selected.
The input signal button connects to the top-level signal
GPIO_BUTTONS_re, which is a low-to-high transition indicator on
the Sine Wave Sequencer button. The output signal Y connects to the top-level signal,
sineSel, which selects the sine wave.