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Home · peterkvt80/vbit2 Wiki · GitHub

 2 years ago
source link: https://github.com/peterkvt80/vbit2/wiki
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Welcome to the vbit2 wiki!

Introduction

VBIT2 together with raspi-teletext implements teletext generation on a Raspberry Pi. VBIT2 handles carousels using a timer for precise timing unlike simpler systems. It also handles all transmission flags so it can be used for subtitles, newsflash and header inhibit etc. It has a system to format various fields such as time into the header and rows. VBIT2 loads files into memory and plays them out from there so it has a very low CPU usage. It has a file monitor which can add, update, and delete pages from memory whenever the corresponding page file is changed.

A page file must be in MRG tti format. VBIT2 takes page files and generates a teletext stream from them. A teletext stream is simply a stream of character data. If you have Vbit hardware you can feed the stream into vbit-py. Experimenters can feed the stream into other software and hardware. VBIT2 can be compiled and run on Windows or Linux. VBIT2 has been tested on Stretch and Buster Raspberry Pi OS.

While you can install VBIT using HDMI, it can only run correctly on composite video. When you want to run VBIT you must switch off. Remove the HDMI cable and connect to your TV using the analogue video port instead and reboot. If you see half a line of flickering dots at the top of the screen you are trying to run VBIT in HDMI mode.

All original form-factor Raspberry Pi models are supported with an appropriate composite video cable. The Raspberry Pi Zero models can be used via their unpopulated 0.1" composite video header connector. The Raspberry Pi 400 keyboard computer cannot be used as it does not provide the required analogue video output.

Installing

These instructions detail how to get a VBIT2 teletext system running on a Raspberry Pi and generating a teletext signal for your TV with raspi-teletext.

Install a recent version of Raspbian as detailed at the download page . Either Raspbian or start with NOOBS and ask it to install Raspbian. Get your Pi online using WiFi or wired ethernet.
The first time you run your Pi it will guide you through setting the language and locale, and get you online.

Installing VBIT2

An install script is provided to set things up for you. From a terminal or console window enter:

source <(wget -O - https://raw.githubusercontent.com/peterkvt80/vbit2/master/getvbit2)

This will download and compile the latest release of VBIT2, raspi-teletext, and start the VBIT2 configuration tool to install a teletext service and set startup options.

There are a couple YouTube videos of people installing the system

If you already have an older version of VBIT2 installed, please follow the instructions on updating.


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