Begin developing FTDI CBUS LED blinky example script

scripting/ftdi.py

+#!/usr/bin/env nix-shell
+#!nix-shell -i python -p "python3.withPackages (p: with p; [pyftdi])" --pure
+
+from time import sleep
+from pyftdi.eeprom import FtdiEeprom
+from pyftdi.ftdi import Ftdi, FtdiError
+
+
+
+print('Hello, FTDI!')
+
+
+
+ftdi = Ftdi()
+
+ftdi.open_from_url('ftdi:///1')
+
+# sanity check: device should support CBUS feature
+# self.assertEqual(ftdi.has_cbus, True)
+
+eeprom = FtdiEeprom()
+eeprom.connect(ftdi)
+
+# sanity check: device should have been configured for CBUS GPIOs
+# self.assertEqual(eeprom.cbus_mask & 0b1001, 0b1001)
+
+# configure CBUS0 and CBUS3 as output
+ftdi.set_cbus_direction(0b1001, 0b1001)
+
+# no input pin available
+# self.assertRaises(FtdiError, ftdi.get_cbus_gpio)
+
+
+frame = 0
+while True:
+  ftdi.set_cbus_gpio(frame & 0b1001)
+
+  frame += 1
+  sleep(0.1)
+