Thank you very much. Sometimes we do not see the simplest solutions ourself.

Hello, I am just converting my project from Mervis 2.0.12 to Mervis 2.2 which is mainly work on the HMI. I am stuck in selecting background images (*.png) for the HMI pages. I see only the default graphics (resources). How can I add my own graphics/images to the resources of the HMI template that I created?

Hi,

the device address in Mervis is decimal (eg. "71" with all DIP switches on EMO set to "On"). The connection via I2C-Bus to UniPi is indicated by a LED below the address DIP switch. This is the hardware side. In Mervis you can check in debugging mode if your solution with EMO-AO5/12 works.
I cannot answer your question regarding HMI, because I only use the PWM channels 4-12 with PI/PID-controller.

Best regards

@tomas_hora I wish all at UniPi.technology a happy new year! and thank you for the answer.

Hello,

I did some tests with the EMO-AO4/12 extension board. I did measure the pwm output frequency of the PWM outputs 5-15. The frequency is 200Hz. According to the datasheet of the PCA9685 the PWM output frequency can be changed from 24Hz (min) to 1526Hz (max) by setting the PRE_SCALE register of the PCA to a different value.
I need a slower PWM frequency (for controlling a heater element). Can I change the frequency with Mervis?

Best Regards,

Matthias

There is a new version of UniPi Mervis OS downloadable (date 2016-06-02). Can I apply the debian security updates normally after mounting the filesystem writable?

There is a new version of UniPi Mervis OS downloadable (date 2016-06-02). Can I apply the debian security updates normally after mounting the filesystem writable?

Tomáš,

the BD13 helped. Thank You.

I have a further question. I want to control heating in this way:

A heating element is controlled by Relay 1, temperature is measured by 1Wire sensor, now I want to set a temperature setpoint (e.g. 90 deg.C) -> "Start" -> heating until reaching the setpoint (measured temp => temp setpoint) -> hold temp for x minutes -> switch off heating.
For holding the temperature I did test the B31_REVERSE_ON_OFF_CONTROL_SEQUENCE, but I don't no how to configure the whole application.

Best regards,

Matthias

I want to configure a timer functionality in Mervis like "press button connected to UniPi Digital In 1 -> switch on Relay 1, start a timer with an adjustable preset of x minutes to off -> switch off Relay 2 after timer runs out"
I did discover a library box called "Lib.Hvac.V1_0.Timer". Unfortunately this box is not listed in the F1 Help of Mervis. The library box uses the local variables "TStart (udint)", "TimeFirstPart (udint)", "TImpMin (udint)", "TimePeriod (udint)" and "Status (sint)". Can someone explain the functionality of this library box, the variables and the usage please?

Best regards,

Matthias

I want to configure a timer functionality in Mervis like "press button connected to UniPi Digital In 1 -> switch on Relay 1, start a timer with an adjustable preset of x minutes to off -> switch off Relay 2 after timer runs out"
I did discover a library box called "Lib.Hvac.V1_0.Timer". Unfortunately this box is not listed in the F1 Help of Mervis. The library box uses the local variables "TStart (udint)", "TimeFirstPart (udint)", "TImpMin (udint)", "TimePeriod (udint)" and "Status (sint)". Can someone explain the functionality of this library box, the variables and the usage please?

Best regards,

Matthias