def tty_tx_ctl(c):
"""
transmits a control character
"""
teletype.tx_ctl(c)
key = 3
GPIO.setup(key, GPIO.IN)
#print(GPIO.input(key))
print(1 - GPIO.input(key))
#b = (1 - GPIO.input(key))
#print(b)
GPIO.add_event_detect(key, GPIO.RISING, bouncetime=130) #add rising edge detection on GPIO 23
a = []
d = 0.020
e = 0.030
s = 0 #ltrs mode by default
tx_ctl('ltrs') #sent printer to letters mode on start
#lookup dictionary for ltrs
asciiltrs_to_binstr = {
'A' : '00011',
'B' : '11001',
'C' : '01110',
'D' : '01001',
'E' : '00001',
'F' : '01101',
'G' : '11010',
'H' : '10100',
'I' : '00110',
'J' : '01011',
'K' : '01111',
'L' : '10010',
def tty_tx_ctl(c): """ transmits a control character """ teletype.tx_ctl(c)