waveshare epaper python raspberry pi.py

# http://www.waveshare.com/wiki/4.3inch_e-Paper

# Using FTDI cable - screen Green to FTDI Orange; screen White to FTDI Yellow

import serial
import binascii
import epd
# epd is from https://github.com/yy502/ePaperDisplay/blob/master/epd.py
# Note, using my FTDI USB serial cable - couldn't get rpi UART on 14/15 to work - writes always hung
rate = 115200
#rate = 9600
ser = serial.Serial(port='/dev/ttyUSB0',baudrate=rate,xonxoff = False,rtscts = False,dsrdtr = False,writeTimeout = 3)
if ser.isOpen():
    print "Writing"
    print epd._cmd_handshake
    ser.write(epd.H2B(epd._cmd_handshake))
    print "Reading"
    print repr(ser.read(2))
    ser.write(epd.H2B(epd._cmd_read_baud))
    print "Reading"
    print ser.read(4)
    print "Done"
    # set baud rate to 9600 in case this helps stop hanging the pi (but it didn't)
    ser.write(binascii.unhexlify("A5 00 0D 01 00 00 25 80 CC 33 C3 3C 0C".replace(" ","")))
    ser.close()

ser = serial.Serial(port='/dev/ttyUSB0',baudrate=9600,xonxoff = False,rtscts = False,dsrdtr = False,writeTimeout = 3)
if ser.isOpen():
    
    #ser.write(binascii.unhexlify("A5 00 0B 10 00 03 CC 33 C3 3C BD".replace(" ","")))    
    #ser.write(binascii.unhexlify("A5 00 11 24 00 0A 00 0A 00 FF 00 FF CC 33 C3 3C 90".replace(" ","")))
    #print "Done"
    #ser.write(binascii.unhexlify("A5 00 17 30 00 0A 00 0A C4 E3 BA C3 57 6F 72 6C 64 00 CC 33 C3 3C 9E".replace(" ","")))
    #print "Done"

    hex_txt = epd.A2H("Hello World")
    x0, y0 = 10, 10
    hex_x0 = ("000"+hex(x0)[2:])[-4:]
    hex_y0 = ("000"+hex(y0)[2:])[-4:]
    hex_size = ("000"+hex(13+len(hex_txt)/2)[2:])[-4:]
    _cmd = epd.FRAME_BEGIN+hex_size+epd.CMD_DRAW_STRING+hex_x0+hex_y0+hex_txt+epd.FRAME_END

    ser.write(epd.H2B(_cmd))

    # This updates the screen; I used to find it also hung the rpi, but that was due to underpowered PSU (0.7a not enough!)
    print ser.write(epd.H2B(epd._cmd_update))
    print "Done update"