reproduces @scanlime's tablet work using GlitchKit instead of the FaceWhisperer

glitchkit_tablet.py

#!/usr/bin/env python2

import sys
import binascii

from greatfet import GreatFET
from greatfet.protocol import vendor_requests as vr

gf = GreatFET()

# Use the ChipWhisperer to clock the GreatFET. Synchronize all the things.
print("Switching to external clock...")
gf.switch_to_external_clock()

# Provide a phase-locked clock to the target from the GreatFET,
# which will be enabled at the same time as VBUS.
print("Spinning up a clock for the target...")
gf.glitchkit.provide_target_clock(gf.glitchkit.usb.VBUS_ENABLED);

# Listen for a single event on J1_P7 to indicate that the device has booted.
# This essentially instructs future commands to wait for device boot before they
# perform their core function.
print("Configuring system...")
gf.glitchkit.simple.watch_for_event(1, [('EDGE_RISING', 'J1_P7')])
gf.glitchkit.use_events_for_synchronization(gf.glitchkit.simple.COUNT_REACHED)

# Trigger when a setup packet is issued.
gf.glitchkit.trigger_on_events(gf.glitchkit.usb.HOST_SETUP_TRANSFER_QUEUED)

# Finally, try the event we're interested in.
print("Waiting for board startup & trigger...")
descriptor = gf.glitchkit.usb.capture_control_in(
    request= gf.glitchkit.usb.GET_DESCRIPTOR,
    value  = gf.glitchkit.usb.GET_DEVICE_DESCRIPTOR,
    length = 18
)
print("Read descriptor: {}".format(binascii.hexlify(bytearray(descriptor))))

# Reset the GreatFET when we're done, for good measure.
gf.reset()