The STM is a VFD (Vacuum Fluorescent. Display) controller/driver that is driven on a 1/4 to. 1/duty factor. It consists of segments output lines, 6 grid . PT is a Vacuum Fluorescent Display (VFD) Controller driven on a 1/4 to 1/11 duty factor. Serial data is fed to PT via a three-line serial interface. It. PT Isolated DC/DC Converters are available at Mouser Electronics. Mouser offers inventory, pricing, & datasheets for PT Isolated DC/DC Converters.
|Published (Last):||11 May 2005|
|PDF File Size:||20.32 Mb|
|ePub File Size:||18.47 Mb|
|Price:||Free* [*Free Regsitration Required]|
PT VFD driver ( segm max), Keyboard scan (24 keys max) | Mbed
By disabling cookies, some features of the site will not work. The grid looks similar to a ”chicken fence”.
The display PCBs were reverse engineered, but used unmodified. It supports dimming brightness control and has additional outputs for 4 LEDs, 4 general purpose inputs and a 6×4 keyboard matrix scan.
The intensity depends on the voltage and the dutycycle. Last commit 20 Jan by Wim Huiskamp. The device has a filament of parallel wires that is heated and emits electrons. When the cathode reference was to be at GND this would is not be sufficient to illuminate the segments.
In some cases the displays also feature additional segments for the decimal point dpcolons or symbols. By continuing to use our site, you consent to our cookies. The diagram below shows the reference schematic for the PT The device also offers 4 general purpose switch inputs and a 6×4 keyboard matrix scan. The second part of the lib provides separate classes for the particular settings needed for three example displays: It has internal memory for all digits and will continuously output that data to the display.
The bit that should be set for each segment is defined separately. These may be set and cleared by the appropriate methods. Examples are the Princeton PT or Sanyo LC controllers that support upto 16 characters in 5×7 dot matrix representation.
This will work because the hardware never receives and transmits data at the pt312 time and because the DOUT is actually an open collector output. The best known types are the seven segment displays e.
They are not cheap, unless produced in large numbers. The lib consists of a class for a low-level PT driver with basic initialisation, digit write operations, LED writes, keyscan read and inputpin reads methods.
When the segment has a positive voltage wrt to the cathode the emitted electrons will hit the phosphor and emit light. Whoa, you are using some pictures from my personal website http: This device can support multiple display modes from 4 digits of 16 segments to 11 digits of 11 segments. There are some mbed libs available for dot matrix type VFD drivers e.
There are libs available for several of the PT family members on the Display Components page here. This solution makes the fonttable flexible so you should be able to modify it for different mappings between PT segment output pins and VFD glass segments. Typically the most positive voltage is Vcc 5V. Access Warning You do not have the correct permissions to perform this operation. By disabling cookies, some features of the site will not work.
Note that VFD segments don’t have to represent 7, 14 or 16 segment digits or icons, but may have almost any shape. Access Warning You do not have the correct permissions to perform this operation. The solution is a negative voltage of about V for the cathode and V for the de-activated Grids and segments. They often support user defined characters UDC as well. The seven segments are usually identified by the characters a-g.
This display shows two 7 segment digits for several of its grids. This library interfaces to a PT VFD controller that supports multiple display modes from 6 digits of 16 segments to 11 digits of 11 segments segm.
Each digit has a separate Grid in front of it. The contact wires are melted into the glass body.