forked from M-Labs/nix-servo
49 lines
1.3 KiB
Python
49 lines
1.3 KiB
Python
|
import time
|
||
|
|
from pyfastservo import adc, dac
|
||
|
|
from pyfastservo.common import (
|
||
|
|
ADC_CH0_HIGH_ADDR,
|
||
|
|
ADC_CH0_LOW_ADDR,
|
||
|
|
CH0_HIGH_WORD_ADDR,
|
||
|
|
CH0_LOW_WORD_ADDR,
|
||
|
|
read_from_memory,
|
||
|
|
write_to_memory
|
||
|
|
)
|
||
|
|
###
|
||
|
|
|
||
|
|
def read_adc():
|
||
|
|
adc_value = adc.read_adc_channel(ADC_CH0_HIGH_ADDR, ADC_CH0_LOW_ADDR)
|
||
|
|
return adc_value
|
||
|
|
|
||
|
|
def write_dac(value):
|
||
|
|
dac.set_dac_output(value)
|
||
|
|
|
||
|
|
def read_dac():
|
||
|
|
high_word = read_from_memory(CH0_HIGH_WORD_ADDR, 1)[0]
|
||
|
|
low_word = read_from_memory(CH0_LOW_WORD_ADDR, 1)[0]
|
||
|
|
return (high_word << 8) | low_word
|
||
|
|
|
||
|
|
def perform_loopback_test(test_value):
|
||
|
|
print(f"Setting DAC output to {test_value}...")
|
||
|
|
write_dac(test_value)
|
||
|
|
time.sleep(0.1) # Allow time for the signal to stabilize
|
||
|
|
|
||
|
|
print("Reading ADC value...")
|
||
|
|
adc_value = read_adc()
|
||
|
|
print(f"ADC readback: {adc_value}")
|
||
|
|
|
||
|
|
print("Reading DAC value...")
|
||
|
|
dac_value = read_dac()
|
||
|
|
print(f"DAC readback: {dac_value}")
|
||
|
|
|
||
|
|
if abs(test_value - adc_value) <= 2 and abs(test_value - dac_value) <= 2:
|
||
|
|
print("Loopback test PASSED!")
|
||
|
|
else:
|
||
|
|
print("Loopback test FAILED!")
|
||
|
|
print(f"Expected: {test_value}, ADC: {adc_value}, DAC: {dac_value}")
|
||
|
|
|
||
|
|
def main():
|
||
|
|
test_value = 0x2000 # Mid-range value (8192 in decimal)
|
||
|
|
perform_loopback_test(test_value)
|
||
|
|
|
||
|
|
if __name__ == "__main__":
|
||
|
|
main()
|