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FAQ's
- Questions and Problems

FAQ's

Questions and Problems

If your question has already been asked then it should appear in the list below, along with fixes or workarounds.

Find a similar problem in the list of FAQs and see if your problem can be resolved.
There is a python script in the root dierectory of the Pipsta examples called verify_pipsta_install.py and this can be run from the Raspbian command line as python verify_pipsta_install.py. This should help in most cases.
If after running verify_pipsta_install.py and perusing all of the FAQs on this page you still can't resolve your issue then please contact Pipsta Support.

Printer LED is Not Illuminating

Check both the power to the printer (on the back of the Pipsta) and the USB connection from Raspberry Pi to printer

Printer LED is Flashing Green

Ensure the paper is loaded correctly

Printer LED is Flashing Green-Off-Red-Off

Ensure the printer power supply is present. Whilst the Raspberry Pi and Printer can communicate with just a USB connection, printing cannot take place without the printer power being applied

Permission Error When Running Python Script

Ensure you copied the system files (found in pipsta/Examples/system_scripts/) to the correct locations
- ls /etc/udev/rules.d/60-ablesystems-pyusb.rules
- ls /etc/modprobe.d/usblp_blacklist.conf

I Get "ImportError: No module named usb.core" when Running the Examples

This is usually the result of PyUSB not having been installed. Refer to page 8 of PIPSTA004 - Pipsta First-Time Setup.

I Get "IOError: Printer not found" when Running the Examples

This is usually the result of the printer not being connected.

I Get "usb.core.USBError: [Errno None] could not reset: Operation not permitted" when Running the Examples

This has been an outstanding issue.

If your Pipsta printer firmware is V9.2.03
1. Please upgrade the firmware to V9.2.09 using the fpu (both can be found in the downloads section of bit bucket.
Then re-install the latest version of the Pipsta examples (download from bitbucket).
Copy the new pipsta/Examples/system_scripts/ to /etc/udev/rules.d/60-ablesystems-pyusb.rules
Restart the Raspberry Pi

If the printer still fails to be discovered then -

Contact support
The following workaround may work.
1. Unplug the printer from the USB port
2. Enter the command sudo lsusb
3. Reconnect the printer
4. Enter the command lsusb (note this is not a sudo command)

To verify that the printer has been detected by the OS enter ls /dev/a* and the response should include /dev/ap1400.

How Do I Upgrade the Pipsta Printer's Firmware?

The fpu can be used to upgrade the Pipsta's firmware. This has been packaged up for Raspbian and placed in the download page of this bitbucket site (along with the new firmware). To install the new firmware follow the instructions below.

Download pipsta-printer-utilities-1.1.1-Linux.deb and V9_2_09.able to your Raspberry Pi.
Install the printer utilities by running sudo dpkg -i pipsta-printer-utilities-1.1.1-Linux.deb from the directory the file is saved in.
Check the install fpu --version
Check the printer is connected to the Raspberry Pi ls /dev/ap1400 or ls /dev/pipsta
cd into the directory containing the downloaded .able file.
Install the new firmware with the command fpu V9_2_09.able

How does NFC work?

NFC (Near-Field Communication) is a short-range, wireless communication interface. This up-coming technology can be found in a variety of applications from the pairing of Bluetooth devices to low-value payments.

In any NFC system, there are two devices. One is the 'reader', the other is the 'tag'. The reader emits a magnetic field which powers the tag, and the tag --once powered-- can communicate with the reader by 'loading' the field: effectively briefly short-circuiting the field and releasing it again to transmit data. The reader reads this 'back-scattered' data by detecting the differences in field strength.

Note that the tag is ordinarily unpowered, i.e. has no battery or power supply, making it small, portable and giving it an improved electrical life over a battery powered tag. Also note that communication ranges are considerably reduced with respect to powered tags as a consequence: the tag can only communicate if it is successfully powered by the reader, and the reader's field-strength falls-off quickly with distance. Ranges of <5cm are typical of NFC communications. Virtues are made of this short communication range as it is perceived to be more secure than --say-- Bluetooth communications which can be 'sniffed' at a distance. There are also reduced opportunities for so-called Man-In-The-Middle (MITM) attacks, where a user believes they have a direct Bluetooth connection to a device, whereas the reality is that they are connected to a malicious device which monitors or collects data but also then forwards the data to and fro to the legitimate device, such that the user's experience is as expected, and they do not perceive that there is anything untoward happening.

Example NFC Systems

1) You may have a credit card that you can tap on a Chip and PIN machine to make (low value) payments. In this scenario, the credit card is the tag, the Chip and PIN machine is the reader.

2) You may have Bluetooth speakers that can be paired 'out-of-band' using NFC. Note that the two interfaces are separate and distinct; NFC has been specifically selected to ameliorate security issues such as MITM attacks by forcing close-range pairing using completely different hardware interfaces.

3) The tag/reader relationship is not always intuitive: take for example a system where there are two powered devices, e.g. where a smart-phone replaces the card in the above Chip and PIN scenario. In this case, the smart phone uses something called 'Card Emulation Mode': the phone is then effectively the tag in the NFC system.

Roles in Pipsta NFC

The Pipsta represents the 'tag' in the tag/reader NFC system, and requires a reader (typically in the form of a smart-phone) to power it. Note that this means the Pipsta is unable to read other tags (as neither device would be generating the magnetic field to power the other.)

If you are still uncertain about Pipsta's NFC operation, or would like more information, please contact us at support@pipsta.co.uk

How can I monitor for print job completion?

Please see this technical bulletin

How can I access accented characters etc.?

This technical bulletin provides example Python code to print an index of such characters in the range 0x80 to 0xFF (hex) 128 to 255 (decimal).

Does Pipsta work with Raspbian Jessie and Wheezy?

Yes. If you have issues with pyusb (which manifest as usb.core errors) there are 2 workarounds.

A Simple Workaround for Jessie

The following one liner should install a pre-release of pyusb which works.

sudo pip install --pre pyusb

If you already have an older version installed you will need to add the `upgrade` flag.

sudo pip install --upgrade --pre pyusb

Please let Pipsta Support know if this approach doesn't work.

The Original Workaround for Jessie

Please refer to this workaround here. In short, the advice is to enter the following into the terminal:

pyusbdir="$(mktemp -d)"
pushd "$pyusbdir"
git clone https://github.com/walac/pyusb
cd pyusb/
git checkout 1.0.0b1
sudo python setup.py install
popd
sudo rm "$pyusbdir" -rfv

Which Raspberry Pi form factors are supported by Pipsta?

The following types are supported out-of-the-box:

Raspberry Pi 1 Model B+

Raspberry Pi 1 Model A+

Raspberry Pi 2 Model B

Raspberry Pi 3 Model B

The following are supported by means of an additional kit:

Raspberry Pi Zero - contact us

These variants can be supported if you download 3d print the data here:

Raspberry Pi 1 Model B

Raspberry Pi 1 Model A

Pipsta is NOT compatible with the following:

Pi Compute Module

Where can I buy more label rolls?

Label rolls are available here.