VFD-220 Two-line by 20-character Serial VFDs
VFD-220s are vacuum fluorescent displays with an advanced serial interface factory-installed. The VFD displays text received serially, and the interface understands common terminal-style formatting instructions (e.g., carriage return, tab, etc.)
In addition to these standard features, VFD-220 has EEPROM memory for storage of a custom startup screen and configuration settings; a screen-saver to prevent premature aging of the VFD; and an automatic bargraph generator with multiple styles.
VFD-220 Features
- Terminal-style control codes for easy programming
- 2400/9600bps serial input with 64-byte buffer
- Configurable screen saver dims the display when inactive to prevent burn-in
- Automatic right-alignment feature for spreadsheet-perfect formatting
- EEPROM storage of settings, startup screen
- Deep inventory for no-lead-time delivery
Basic Specifications
| Power Requirements | 4.8 to 5.25Vdc at 300mA max |
|---|---|
| User Connector | 5-pin header, 0.025in. posts on 0.10in. centers |
| Connector Pinout | +5V Gnd Serial Gnd +5V |
| Serial Input | RS-232 (negative swing OK) or inverted TTL, 2400 or 9600bps |
| Operating/Storage Temperature | -20° to 70° C |
| Operating Humidity | 20 to 80% RH, non-condensing |
Dimensions (in mm)
Total depth (front of screen to tips of interface header pins) is 30mm.
| A | y offset edge to hole center (top & bottom) | 4.00 |
|---|---|---|
| B | y pcb height | 37.00 |
| C | y hole spacing | 29.00 |
| D | y display area | 11.50 |
| E | y character height | 4.70 |
| F | x character width | 2.40 |
| G | x offset pcb edge to hole center | 4.00 |
| H | x screen frame (glass envelope) | 95.30 |
| I | x display area | 70.80 |
| J | x hole spacing | 108.00 |
| K | x pcb width | 116.00 |
| L | y frame height (glass envelope) | 25.35 |
| - | mounting hardware size | 4-40 |
| - | screen depth | 14.00 |
VFD Instructions
The VFD-220 works like a mini-terminal, displaying text and responding to traditional control characters like linefeeds, carriage returns, tabs, etc. Its instruction set also includes shortcuts like automatic right-alignment and bargraphs, etc. VFD-specific features include screen saver, brightness control, and EEPROM storage of a startup screen and configuration settings.
| VFD Instruction (ctrl code) | ASCII | Hex |
|---|---|---|
| Null; ignored but may be used for timing (ctrl-@) | 0 | 0x00 |
| Home cursor (ctrl-A) | 1 | 0x01 |
| None (ctrl-B) | 2 | 0x02 |
| End right-alignment (ctrl-C) | 3 | 0x03 |
| Hide cursor (ctrl-D) | 4 | 0x04 |
| Show underline cursor (ctrl-E) | 5 | 0x05 |
| Show blinking-block cursor (ctrl-F) | 6 | 0x06 |
| Pulse piezo buzzer output (ctrl-G) | 7 | 0x07 |
| Backspace (ctrl-H) | 8 | 0x08 |
| Tab: jump to next multiple-of-4 column (ctrl-I) | 9 | 0x09 |
| Smart linefeed: move down one row (ctrl-J) | 10 | 0x0A |
| Vertical tab: move up one row (ctrl-K) | 11 | 0x0B |
| Formfeed: clear the screen (ctrl-L) | 12 | 0x0C |
| Carriage return: move to beginning of next line (ctrl-M) | 13 | 0x0D |
| Turn VFD driver on (ctrl-N) | 14 | 0x0E |
| Turn VFD driver off (ctrl-O) | 15 | 0x0F |
| Accept cursor-position data (next byte) (ctrl-P) | 16 | 0x10 |
| Clear column (ctrl-Q) | 17 | 0x11 |
| Accept right-alignment data (ctrl-R) | 18 | 0x12 |
| Ignored | 19-26 | 0x13-0x1A |
| Escape character: begin multipart instruction* | 27 | 0x1B |
| ESC D n B0-B7 defines custom character n with bit patterns from bytes B0-B7 | ||
| ESC E n displays custom screen (n=0) or restores custom characters (n=1) | ||
| ESC W B0-B7 writes eight bytes of configuration data to EEPROM | ||
| ESC X 0 writes VFD text to EEPROM as custom screen | ||
| ESC n sets VFD brightness in 25% increments (n= 0-3) | ||
| ESC = {style}{width}{value} generates a bargraph (style is A-H indicating type of bargraph; width is width in characters of the graph; and value is the number of bars to be lit. | ||
Accessories
- BSW-CBL wiring harness, 12" power, ground and serial wires to breadboard pins
- PDI-CBL wiring harness, HD-style power connector, DE-9 female for PC internal hookup
- PDX-CBL wiring harness, power, ground wires and DE-9 female for PC external hookup