--- /dev/null
+/**
+ * 5_fir_differentiator.cpp
+ * Written by Clyne Sullivan.
+ *
+ * Does an FIR differentiation on the incoming signal, so that the output is representative of the
+ * rate of change of the input.
+ * A scaling factor is applied so that the output's form is more clearly visible.
+ */
+
+adcsample_t *process_data(adcsample_t *samples, unsigned int size)
+{
+ constexpr int scaling_factor = 4;
+ static adcsample_t output[SIZE];
+ static adcsample_t prev = 2048;
+
+ // Compute the first output value using the saved sample.
+ output[0] = 2048 + ((samples[0] - prev) * scaling_factor);
+
+ for (unsigned int i = 1; i < size; i++) {
+ // Take the rate of change and scale it.
+ // 2048 is added as the output should be centered in the voltage range.
+ output[i] = 2048 + ((samples[i] - samples[i - 1]) * scaling_factor);
+ }
+
+ // Save the last sample for the next iteration.
+ prev = samples[size - 1];
+
+ return output;
+}
+
+++ /dev/null
-/**
- * 5_iir_differentiator.cpp
- * Written by Clyne Sullivan.
- *
- * Does an IIR differentiation on the incoming signal, so that the output is representative of the
- * rate of change of the input.
- * A scaling factor is applied so that the output's form is more clearly visible.
- */
-
-adcsample_t *process_data(adcsample_t *samples, unsigned int size)
-{
- constexpr int scaling_factor = 4;
- static adcsample_t prev = 2048;
-
- // Compute the first output value using the saved sample.
- samples[0] = 2048 + ((samples[0] - prev) * scaling_factor;
- // Save the last sample for the next iteration.
- prev = samples[size - 1];
-
- for (unsigned int i = 1; i < size; i++) {
- // Take the rate of change and scale it.
- // 2048 is added as the output should be centered in the voltage range.
- samples[i] = 2048 + ((samples[i] - samples[i - 1]) * scaling_factor);
- }
-
- return samples;
-}
-