Schematic nomenclature

[MickeyReilley]

I'm not clear on how to read the schematic provided for the mikromedia 7 FPI capacitive board. As an example, I'm trying to figure out how I'm expected to control the backlight.

In the attachment "Grey arrow boxes.jpg" I have circled in red three grey pointer boxes labeled BCKL, VLED+, and VLED-. What does this grey arrow box indicate?

If I search the entire schematic for these words, they show up in a variety of places. As an example BCKL shows up in:

• Capacitive_Display.SchDoc

• Power Supply.SchDoc

• LED driver

What are these three things?

I don't see anything that ties the backlight to the MCU, so I don't know how to turn it on and adjust the brightness. I suspect I'm not properly understanding the schematic nomenclature, so I thought I'd ask these clarifying questions.

[filip]

Hi,

The backlight is controlled via PWM using the LCD_PWM pin of the MCU that is mounted to the mikromedia board.

For example if you are using STM32F407ZG MCU and its MCU card, then the LCD_PWM pin will be located on the PC9 pin, have a look at the schematic :
https://download.mikroe.com/examples/fu ... ematic.pdf

VLED + and - pins are used to supply the backlight with power, while the BCKL-LCD_PWM is used to control the brightness.

Regards,
Filip.