NXYI2C Python sample (for Raspberry Pi)

This is a sample of a clock using NXYI2C. It just shows the system time to 4 nixie tubes. Displays hours and minutes to the four NXYI2C at I2C addresses 21 through 24.

Setup as service

Run the following command on your Raspberry Pi.

curl https://www.nixielive.com/setup-nxyi2c-python-clock.sh | bash

This command will install the following tools at first

• git
• python3-smbus:armhf

Then, copy files

• Copy nxyi2c-python-clock.py to /usr/local/bin.
• Copy nixielive-clock.service to /etc/systemd/system.

Then, register nixielive-clock.service as a service

Program description (nxyi2c-python-clock.py)

This is a really simple program that just gets the system time as a string in the format HHMM (00:00-23:59) and sends it to NXYI2C for each digit.

Time string

In the following program, the system time is formatted by %H%M. If you change this to %m%d, it may become a calendar.

dt_now = datetime.datetime.now()
dt_str = dt_now.strftime('%H%M')

I2C address

Since the I2C address is used from 21 (HEX:15), 21 is hard-coded. If you want to use a different I2C address, please change this part.

# set pattern
bus.write_word_data(21 + i, 1, 2)

Also, check Default firmware sketch of NXYI2C for more information about the values used for each argument of write_word_data.

Display pattern

When changing the number to be displayed, it is shown in a fade-in pattern. The following code has the following meaning

# set pattern
bus.write_word_data(21 + i, 1, 2)

• command = 1 : set pattern
• value = 2 : Fade in

Duration

Specifies how long it will take to complete the pattern.

# set duration
bus.write_word_data(21 + i, 2, 1000)

• command = 2 : set duration
• value = 1000 : ms

Display number

Specifies the number to be displayed on the Nixie tube.

# set number
bus.write_word_data(21 + i, 3, int(c))

• command = 3 : set number
• value : Numbers to be displayed on Nixie tubes

Start changing the numbers

Start changing the numbers to be displayed with what you have specified in the previous commands.

# set start
bus.write_word_data(21 + i, 0, 0)

• command = 0 : start
• value : ignored