4 digit display, colon

I’ve been experimenting with the 4 digit display and have got it to output the current time. However, I’m having trouble getting it to show a colon. I’m likely missing something simple but I’ve been staring at the code on GitHub for far to long. How do I display the 8th bit?

# Grove 4 Digit Display - set 7 individual leds of a segment
# segment: (0-3)
# leds: (0-255) or (0-0xFF) one bit per led, segment 2 is special, 8th bit is the colon
def fourDigit_segment(pin, segment, leds):
	write_i2c_block(address, fourDigitIndividualLeds_cmd + [pin, segment, leds])
	return 1

If I’m reading that right then you have 0-3 being the digits and somehow if I assign fourDigit_segment 8 bits I should get a colon, I’m also wondering what is special about segment 2.

Here is the code I’m using for the clock:

import time
from datetime import datetime
import grovepi

# Connect the Grove 4 Digit Display to digital port D5
displayPin = 5
displayBrightness = 8

while True:
        currentTime = datetime.now().strftime( "%H%M" ) #get current time
        timeArray = map( int,str( currentTime ) ) #map to array
        grovepi.fourDigit_init( displayPin ) #initalize
        grovepi.fourDigit_brightness( displayPin,displayBrightness ) #set brightness

        grovepi.fourDigit_digit( displayPin,0,timeArray[0] ) #first digit
        grovepi.fourDigit_digit( displayPin,1,timeArray[1] ) #second digit
        grovepi.fourDigit_digit( displayPin,2,timeArray[2] ) #third digit
        grovepi.fourDigit_digit( displayPin,3,timeArray[3] ) #fouth digit

        #flash on and off the colon every half second
        grovepi.fourDigit_segment( displayPin,4,11111111 )
        grovepi.fourDigit_segment ( displayPin,4,00000000 )

    except KeyboardInterrupt:
        grovepi.fourDigit_off( displayPin )
    except IOError:
        print ("Error")

I know the problem is with the segment code just not sure where to go to fix it. Any help would be much appreciated.

I’ll try out the example on the 4 digit display and see if the colon works and get back to you shortly.