Blog

New product - TWILCD 40x2/40x4/RGB edition

2012.4.6

twilcd2

We are happy to introduce a new product in our linup of TWI/I2C display controllers. The newcomer is a variant of our fancy TWILCD character LCD backpack that allows you to control displays that use the popular HD44780 chip using just two data lines.

The original version of TWILCD (which we will refer to as "TWILCD (Standard) from now on) supported a variety of the most common display connectors: 1x16, 1x14+2, 2x7 and 2x7+2. Although the board worked really well for these kinds of connectors, we eventually found out (thanks to excellent user feedback!) that there were some displays that we couldn't support.

The biggest missing feature in the original TWILCD, it turns out, was support for big 40x4 displays. Although these displays also utilize the HD44780 chip, they are quite a bit different. First of all, they use a 2x9 connector that has a completely different pinout from the 2x7 and 2x8 connectors. Also, since the HD44780 chip can only support a maximum of 40x2 characters, 40x4 displays actually have two HD44780 chips, making them very cumbersome to use with the standard LiquidCrystal library.

We've added seamless support for 40x4 in our new TWILCD board: Just set it up with lcd.begin(40, 4) and the TWILCD will take care of the rest (making sure to update both HD44780 chips correctly).

We also wanted to supportNewhaven's 16x2 RGB displays so we included a 1x18 header and the necessary passive components to take full advantage of the RGB backlight. With the function lcd.setRGB(R, G, B) you can set the backlight color between 0 and 255 for every color. The TWILCD controller takes care of PWM the three colors seperatly.

We also added a 2x8 connector, which some backlit displays have.

You can now buy the new TWILCD with either bundled with the RGB display or as a board-only from our store.

Newhaven 40x4 displays work well with the TWILCD, as should any other 40x4 display that uses the 2x9 header.

We've updated the assembly instructions to make it easy to chose the right version of TWILCD for your display!