Matrix Orbital VK204-25 VFD

Matrix Orbital, manufacturers of probably the finest add-on displays available to the modder today have a range of VFDs perfectly suited for the modder. Here, I am going to take a look at a VFD from their range, in particular the VK204-25. This a 20 character x 4 line alphanumeric display sporting a connector for a 25 way keypad and 6 general purpose outputs capable of controlling 5V loads up to 20mA each. The keypad and outputs are controlled by software which you may need to write yourself, although software to do this is now starting to appear. Check out the Matrix Orbital site and Forum to see what is available. The unit is connected to the computer via a serial port. Depending on the model, the display also requires either a 5V or 12V supply.

VK204-25 Specifications:

Appearance
20 characters x 4 lines
Module size: 98.0mm(L) x 60.0mm(W) x 24.4mm(T)
Display size: 70.8mm(L) x 20.9(W)
Character size: 2.4 x 4.7mm
Bluish green illumination
Four software controlled brightness settings

Interfaces
Interface with up to a 25-key keypad
Use 6 - General Purpose Output
Communicate over RS232 or I2C (Connect up to 16 displays over I2C)

Speed
RS232 mode : Five baud rates to 19.2 Kbps
I2C mode: Serial transfers of up to 100 Kbps

Functional Capabilities
Display text, large digits, and bar graphs
Software controlled line wrapping, scrolling, brightness, and time-out setting (up to 180 minutes)
Easily add a filter for outdoor use
Available in a PC drive bay insert
Software and manual on CDROM

Power Requirements (Ta = 25°C, Vin = 5.0V)
Operates at -20ºC to +70ºC
Supply Voltage: +4.75 to +5.25Vdc
Wide Voltage Option: +7 to +15Vdc
Supply Current (Power off): 25mA typical
Supply Current (Power up): up to 550mA inrush
Supply Current (Power on): 290mA typical
The display as it comes in all it's nakedness.

Included in the pack is a disk containing the on-line manual and software to control the display. The serial and power cable is not included as standard and has to be bought separately. The supplied software is mostly shareware or freeware and I would suggest checking with the software authors for updates. All Matrix Orbital VFD displays where possible, share the same control codes as the LCDs and as such can generally use the same software.