From 0927824c614531f41a009fbc02231d78ab06068f Mon Sep 17 00:00:00 2001
From: Florian Agbuya <fa@m-labs.ph>
Date: Thu, 29 Aug 2024 17:16:10 +0800
Subject: [PATCH] test write_sample

---
 fast-servo/pyfastservo/dac.py | 52 +++++++++++++++++++++++++++++------
 1 file changed, 43 insertions(+), 9 deletions(-)

diff --git a/fast-servo/pyfastservo/dac.py b/fast-servo/pyfastservo/dac.py
index cb9d5a7..617047f 100644
--- a/fast-servo/pyfastservo/dac.py
+++ b/fast-servo/pyfastservo/dac.py
@@ -100,16 +100,30 @@ def power_down(channel, power_down=True):
     reg_contents = read_from_memory(CTRL_ADDR, 1)[0]
     print(f"REG contents: 0b{reg_contents:03b}")
 
-def set_dac_output(value):
-    value = min(value, 0x3FFF)
-    low_word = value & 0xFF
-    high_word = (value >> 8) & 0x3F
+# def set_dac_output(value):
+#     value = min(value, 0x3FFF)
+#     low_word = value & 0xFF
+#     high_word = (value >> 8) & 0x3F
+
+#     write_to_memory(CH0_HIGH_WORD_ADDR, high_word)
+#     write_to_memory(CH0_LOW_WORD_ADDR, low_word)
+#     write_to_memory(CH1_HIGH_WORD_ADDR, high_word)
+#     write_to_memory(CH1_LOW_WORD_ADDR, low_word)
+#     print(f"DAC output set to: 0x{value:04X}")
+
+def write_sample(channel, sample):
+    assert channel in (0, 1)
+    if channel == 0:
+        addresses = [CH0_HIGH_WORD_ADDR, CH0_LOW_WORD_ADDR]
+    else:
+        addresses = [CH1_HIGH_WORD_ADDR, CH1_LOW_WORD_ADDR]
+
+    low_word_value = sample & 0xFF
+    high_word_value = (sample >> 8) & 0x3F
+    values = [high_word_value, low_word_value]
+    for addr, value in zip(addresses, values):
+        write_to_memory(addr, value)
 
-    write_to_memory(CH0_HIGH_WORD_ADDR, high_word)
-    write_to_memory(CH0_LOW_WORD_ADDR, low_word)
-    write_to_memory(CH1_HIGH_WORD_ADDR, high_word)
-    write_to_memory(CH1_LOW_WORD_ADDR, low_word)
-    print(f"DAC output set to: 0x{value:04X}")
 
 def configure_ad9117():
     spi = spidev.SpiDev()
@@ -134,6 +148,26 @@ def configure_ad9117():
         power_down(1, False)
         manual_override(True)
 
+        # Write sample value 0x1FFF to both channels
+        sample_value = 0x1FFF
+        write_sample(0, sample_value)  # Write to channel 0
+        write_sample(1, sample_value)  # Write to channel 1
+
+        print(f"Sample value 0x{sample_value:04X} written to both channels")
+
+        # Read back the values from memory
+        ch0_high = read_from_memory(CH0_HIGH_WORD_ADDR, 1)[0]
+        ch0_low = read_from_memory(CH0_LOW_WORD_ADDR, 1)[0]
+        ch1_high = read_from_memory(CH1_HIGH_WORD_ADDR, 1)[0]
+        ch1_low = read_from_memory(CH1_LOW_WORD_ADDR, 1)[0]
+
+        # Reconstruct the 14-bit values
+        ch0_value = (ch0_high << 8) | ch0_low
+        ch1_value = (ch1_high << 8) | ch1_low
+
+        print(f"Read back value for channel 0: 0x{ch0_value:04X}")
+        print(f"Read back value for channel 1: 0x{ch1_value:04X}")
+
         print("AD9117 configuration completed successfully")
         return True