The SparkFun SerLCD is an AVR-based, serial enabled LCD that provides a simple and cost effective solution for adding a 20x4 Black on RGB Liquid Crystal Display into your project. We've seriously overhauled the PCB design on the back of the screen by including an ATmega328P that handles all of the screen control, meaning a backpack is no longer needed! This display can now communicate in three different ways: serial, I2C, and SPI. This simplifies the number of wires needed and allows your project to display all kinds of text and numbers.
The on-board ATmega328P AVR microcontroller utilizes 11.0592 MHz crystal for greater communication accuracy with adjustable baud rates of 1200 through 1000000 but is default set at 9600. The firmware for this SerLCD is fully opensource and allows for any customizations you may need.
Note: Since the SerLCD is a 3.3V device, please make sure you convert to 3.3V logic depending on your chosen microcontroller or single board computer. Otherwise, you may risk damaging your board.
This skill defines how difficult the soldering is on a particular product. It might be a couple simple solder joints, or require special reflow tools.
Skill Level: Noob - Some basic soldering is required, but it is limited to a just a few pins, basic through-hole soldering, and couple (if any) polarized components. A basic soldering iron is all you should need.
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If a board needs code or communicates somehow, you're going to need to know how to program or interface with it. The programming skill is all about communication and code.
Skill Level: Rookie - You will need a better fundamental understand of what code is, and how it works. You will be using beginner-level software and development tools like Arduino. You will be dealing directly with code, but numerous examples and libraries are available. Sensors or shields will communicate with serial or TTL.
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If it requires power, you need to know how much, what all the pins do, and how to hook it up. You may need to reference datasheets, schematics, and know the ins and outs of electronics.
Skill Level: Rookie - You may be required to know a bit more about the component, such as orientation, or how to hook it up, in addition to power requirements. You will need to understand polarized components.
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Based on 8 ratings:
1 of 1 found this helpful:
I was looking for a display to go with some Qwiic components and this fit the bill perfectly. I soldered a Qwiic adapter on the I2c pins and it was good to go.
Good looking display to be used for a readout on my MPD music player. Straight serial for ease of interfacing (3 wires) to a Raspberry Pi (did not want to use I2c because it is also being used to control volume to the DAC chip).
I would encourage SparkFun to please ship these units with the latest firmware. It took me a while to realize that was why the '+ RGB' command was not functioning. Then I had to cobble together a serial programming interface to update it.
All is fine now and working. Time to plunge into Python programming land, one more thing I know nothing about.
Fantastic tool for quick out of the box serial display away from a terminal. In our case we need 115200 for some specific purposes, but have not been able to get the speed switched. Documentation and firmware source code says it's an option and well within range since it has the 11.xxx MHz oscillator, but we have not been able to get it to switch to any other speed. Stuck at 9600.
Might just need a firmware update... but why would a device be shipping with a firmware which is months out of date? Excess inventory, or production just hasn't gotten the right hex file to load. In either case, it's keeping it from getting 5 stars.
Static power consumption runs about 5mA with the back light off measured on a Rigol digital supply. I was rather pleased with that power level.
The PDF documentation of the SerLCD is rather old. It is applicable, though missing the speeds which are shown in the source code on GitHub and mentioned in the product description.
I chose this display because of the SPI interface and the fact it has four lines and twenty characters per line. I found that the the SPI clock needed to be around 54 kHz (or at least well under 100kHz) to eliminate flicker and have a stable display. Just stretching the delay times after sending commands did not help with the flicker Also, when I used the backlight setting commands to set the backlight (0x80 - 0xD9), I wasn't able to disable the backlight display messages with the Disable System Messages command (0x2F). Instead I used the Set RGB Backlight Command (0x2B) which doesn't display system messages when used. Overall, it's a nice display and I like the SPI interface.
Worked fine for two weeks, then dead. Not the CPU as other displays worked in its place.
Sorry to hear you're having trouble! Please contact our technical assistance team for help with your display.
This is a great product. The only thing I can suggest, is to add an automatic and programmable ambient light dimming circuit with a photo sensor. As an alternative, it would be nice to have a digital and analog pin as a breackout.
I tried using this with I2C and pi4j on a raspberry pi, and it just didn't work well. There was some sort of comm error happening that corrupted the display. Perhaps the serial interface works, but the i2c doesn't.