dac: update unit-test docs and examples for driver-NG

examples/peripherals/dac/dac_basic/pytest_dac_basic.py

@@ -0,0 +1,34 @@
+# SPDX-FileCopyrightText: 2021-2022 Espressif Systems (Shanghai) CO LTD
+# SPDX-License-Identifier: CC0-1.0
+
+import pytest
+from pytest_embedded import Dut
+
+
+@pytest.mark.esp32
+@pytest.mark.esp32s2
+@pytest.mark.generic
+def test_dac_basic_example(dut: Dut) -> None:
+    res = []
+    for _ in range(10):
+        res.append(dut.expect(r'DAC channel 0 vaule:( +)(\d+)(.*)DAC channel 1 vaule:( +)(\d+)', timeout=10))
+
+    avg1_ch1 = 0
+    avg1_ch2 = 0
+    avg2_ch1 = 0
+    avg2_ch2 = 0
+
+    for val in res[0:5]:
+        avg1_ch1 = avg1_ch1 + int(val.group(2))
+        avg1_ch2 = avg1_ch2 + int(val.group(5))
+    for val in res[5:10]:
+        avg2_ch1 = avg1_ch1 + int(val.group(2))
+        avg2_ch2 = avg1_ch2 + int(val.group(5))
+
+    avg1_ch1 = int(avg1_ch1 / 5)
+    avg1_ch2 = int(avg1_ch2 / 5)
+    avg2_ch1 = int(avg2_ch1 / 5)
+    avg2_ch2 = int(avg2_ch2 / 5)
+
+    assert avg2_ch1 > avg1_ch1
+    assert avg2_ch2 > avg1_ch2