[ProMini] Blue LED on Pin 13 wont turn off

[sundberg84]

@rollercontainer - could be, some bootloaders use this led to indicare its ready.
Arduino Pro Mini bootloader for example blinks if its loaded and waiting for a sketch to be uploaded. Depends on which bootloader you use and how that is coded.
But once you upload a sketch on the original bootloader it does not blink (unless there is radio traffic - ie signals going to and from the nrf24l01+ on pin 13.

[rollercontainer]

You are right, I missed that one. 13 is a radio pin AND the led output. So I have to move the radio pin or desolder the led, right?

[mfalkvidd]

I keep the led13 on my battery-powered units. It is useful for basic troubleshooting and the power used is small enough to be ignored.

[rollercontainer]

@sundberg84 Thanks a lot for opening my eyes!

I moved the radio to soft spi and now it works like intended.

#define MY_DEBUG
#define MY_RADIO_NRF24
// RobotDyn Pro Mini 3,3V 8Mhz has blue LED on Pin13 which is used by radio and will be lit all the time.
// Therfore, I moved the radio as it is done for the ethernet gateway.
#define MY_SOFTSPI
#define MY_SOFT_SPI_SCK_PIN 14  // Analog 0
#define MY_SOFT_SPI_MOSI_PIN 15 // Analog 1
#define MY_SOFT_SPI_MISO_PIN 16 // Analog 2
#define MY_RF24_CE_PIN 5
#define MY_RF24_CS_PIN 6

#define SKETCH_NAME __FILENAME__
#define SKETCH_DATE __DATE__
#define MY_NODE_ID 70
#define MY_PARENT_NODE_ID 0
#define MY_REPEATER_FEATURE false

[boozz]

@rollercontainer

And you opened my eyes with the soft-spi remark. I just realized this could be an option to connect a LCD to a pro-mini as some kind of temperature indicator for multiple sensors. This is still on my wish-list.

• outside temperature (low, high, current).
• multiple room temperatures
• etc..

Thanks,

BR,

Boozz

[rollercontainer]

How about an I2C Display? Two wires on A4 &A5...

[sundberg84]

Going OT now - but @boozz here is an example of my i2c lcd (A4 + A5).
https://www.openhardware.io/view/23/In-wall-LCD-SwitchScene-controller-for-MySensors

[boozz]

@sundberg84

Thanks for the example, I'll have a look at it and yes we're going OT now. :grin:

BR,

Boozz

[rollercontainer]

no problem, my fault was solved. Feel free to capture the thread ^^

[mfalkvidd]

Another thing that's slightly OT... How much more power does soft spi use compared to hardware spi? Is it more or less than the led?

[rollercontainer]

Excellent question. I dont know.

[rollercontainer]

Here are some scientific messurements: http://cc.oulu.fi/~kmikhayl/site-assets/pdfs/2012_NTMS.pdf

Table on last page says: SoftSPI consumes about double the electricity of a Hardware SPI on a PIC system. So, desoldering the LED is the thing to do.

Thx for the hint.