Merge pull request #497 from adafruit/dacx578

adding DACx578

Author: FoamyGuy

.gitmodules

@@ -1058,3 +1058,6 @@
 [submodule "libraries/helpers/display_analogclock"]
 	path = libraries/helpers/display_analogclock
 	url = https://github.com/adafruit/Adafruit_CircuitPython_Display_AnalogClock.git
+[submodule "libraries/drivers/dacx578"]
+	path = libraries/drivers/dacx578
+	url = https://github.com/adafruit/Adafruit_CircuitPython_DACx578.git

docs/drivers.rst

@@ -506,6 +506,7 @@ These provide functionality similar to ``analogio``, ``digitalio``, ``pulseio``,
     AW9523 GPIO expander and LED driver (adafruit_aw9523) <https://docs.circuitpython.org/projects/aw9523/en/latest/>
     Crickit Robotics Boards (adafruit_crickit) <https://docs.circuitpython.org/projects/crickit/en/latest/>
     CST8XX Capacitive Touch (adafruit_cst8xx) <https://docs.circuitpython.org/projects/cst8xx/en/latest/>
+    DACx578 8 x Channel 12-Bit DAC (adafruit_dacx578) <https://docs.circuitpython.org/projects/dacx578/en/latest/>
     DS2413 OneWire GPIO Expander (adafruit_ds2413) <https://docs.circuitpython.org/projects/ds2413/en/latest/>
     FocalTech Capacitive Touch (adafruit_focaltouch) <https://docs.circuitpython.org/projects/focaltouch/en/latest/>
     HX711 24-bit ADC (adafruit_hx711) <https://docs.circuitpython.org/projects/hx711/en/latest/>