Important changes to forums and questions
All forums and questions are now archived. To start a new conversation or read the latest updates go to forums.mbed.com.
9 years, 11 months ago.
Has anyone used Olimex SHIELD-LCD16x2 with mbed?
This is the device I have ( https://www.olimex.com/Products/Duino/Shields/SHIELD-LCD16x2/open-source-hardware )
I don't see any libraries for it yet but wanted to ask first instead of re-inventing the wheel. It uses 2 analog and 2 digital lines of the Arduino connector.
My mbed board is an STM Nucleo if it makes any difference to anyone.
2 Answers
9 years, 11 months ago.
This display is defaulted to i2c communication via the PIC MCU which drives the display so it can not be directly driven from a Mbed MCU using the popular Mbed libraries unless you can isolate the PIC MCU, if you search Mbed there may be someone who has used this and produced a library to drive it but unlikely. Otherwise download the 'DEMO' code from Olimex and have a look to see if you can convert the display drive functions to work on Mbed. These may well be quite simple to implement to send text characters to the display. Then yes it is a case of redesigning the wheel putting together a library to drive this display using the specific PIC MCU commands.
Thanks. That is what I thought was going to have to happened but wanted to be sure before I invested the time. I chose this specific display because it required so few lines on the connector and because all the code is available even down to the firmware. I now have something to keep me busy this weekend.
posted by 14 Jan 2015
9 years, 11 months ago.
Hello,
the display has hd44780 controller, you will find many libraries on mbed (like TextLCD), just search for hd44780.
Regards, 0xc0170
I was referring more towards the module it's self. It's an i2c or uart module and you do not communicate with it quite the same as if you were using a raw lcd. A library for this would probably need to include/expand on TextLCD. This is different from say the Sparkfun LCD Button shield that uses separate. lines for the LCD and buttons. It looks like I need to write a library that will make it easy to reuse this shield with various projects.
posted by 14 Jan 2015The shield has its own PIC controller that interfaces with the HD44780 and the buttons. You will have to implement the protocol that the shield uses. The hardware interface is either serial or I2C. The nucleo should be able to support either of those. However, the pins that are used by the shield for serial are D0/D1 which are not connected out of the box on the nucleo since they are used for the USB serial interface. The I2C pins on the A connector also dont default to one of the nucleo I2C pins. So in addition to writing the software you may also have to do some hardware modifications to the shield before it works with the nucleo.
posted by 14 Jan 2015