new mode --bin24

tests/test_processing.py

@@ -13,6 +13,7 @@ from rfg_adc_plotter.gui.pyqtgraph_backend import (
     build_logdet_voltage_fft_input,
     build_main_window_layout,
     coalesce_packets_for_ui,
+    TTY_CODE_SCALE_DENOM_24,
     compute_background_subtracted_bscan_levels,
     compute_aux_phase_curve,
     compute_do1_tagged_aggregate,
@@ -87,6 +88,26 @@ class ProcessingTests(unittest.TestCase):
         self.assertTrue(np.all(volts >= -5.0))
         self.assertTrue(np.all(volts <= 5.0))
 
+    def test_convert_tty_i16_to_voltage_int24_denominator_maps_full_scale(self):
+        full_scale = float(TTY_CODE_SCALE_DENOM_24)
+        codes = np.asarray([-full_scale - 1.0, 0.0, full_scale], dtype=np.float32)
+        volts = convert_tty_i16_to_voltage(codes, 5.0, denom=TTY_CODE_SCALE_DENOM_24)
+
+        self.assertAlmostEqual(float(volts[0]), -5.0, places=4)
+        self.assertAlmostEqual(float(volts[1]), 0.0, places=6)
+        self.assertAlmostEqual(float(volts[2]), 5.0, places=4)
+
+        # A quarter-scale 24-bit code must yield ~1.25 V with the int24 denom, but the
+        # default int16 denom over-scales it ~256x and clips to the ±5 V range. This
+        # guards that --bin24 uses the wider full-scale rather than the int16 one.
+        quarter = np.asarray([full_scale / 4.0], dtype=np.float32)
+        self.assertAlmostEqual(
+            float(convert_tty_i16_to_voltage(quarter, 5.0, denom=TTY_CODE_SCALE_DENOM_24)[0]),
+            1.25,
+            places=4,
+        )
+        self.assertAlmostEqual(float(convert_tty_i16_to_voltage(quarter, 5.0)[0]), 5.0, places=6)
+
     def test_build_logdet_voltage_fft_input_converts_codes_and_exponentiates(self):
         codes = np.asarray([-32768.0, 0.0, 32767.0], dtype=np.float32)
         volts, fft_input = build_logdet_voltage_fft_input(codes, 5.0)