Pull-up or Pull-down

In electronic logic circuits, a pull-up resistor or pull-down resistor is a resistor used to ensure a known state for a signal (wiki).

  • Pull-up – this option enables the internal pull-up resistor. For GPIO inputs, it means that the pressed state is the LOW signal (connected to the ground).
  • Pull-down – For GPIO inputs, it means that the pressed state is the HIGH signal (connected to +3.3V via a 4700 Ohm resistor). You cannot mix internal pull-up or pull-down resistors on the same port.
  • External pull-up – similar to the internal pull-up resistor, but you should add it externally on your PCB. It is the main disadvantage. The main advantage, you may mix different pull-up or pull-down types on the same port. A typical resistor value is 4700 Ohm.
  • External pull-down – see notes above.

What should you select? It depends on your application and a used external sensor. For GPIO inputs, I prefer “pull-up.” For external sensors, you should look at the sensor’s data sheet for recommended schematics.

Note (CC2530, CC2531): The internal pull-up or pull-down option enabled for one pin automatically selects the same mode for all other pins on the same port P0x, P1x, or P2x. It is the main disadvantage because if you, for example, enable the internal resistor on P0.1, you enable it on P0.2 – P0.7. Therefore, it adds limits for mixing different sensors on the same port.

Note (CC2530, CC2531): P10 and P11 pins do not have internal pull-up resistors. Pull-up or pull-down mode does not affect it. I recommend using an external pull-up or external pull-down mode.

GPIO inputs

Inversed – By default, the firmware interprets the LOW state on the input pin as a button’s pressed state. If this option is enabled, the HIGH state means the pressed button. This option work in junction with the pull mode. For example, if you select the pull-down mode and set the “inversed” option, the logic is twice inverted, the firmware will interpret the LOW state on the input as a button’s pressed state.

Link – The input immediately controls the linked output state (e.g., Input 1 – Output 1). The device sends the on/off state of the output to a coordinator. Otherwise, the input is independent.

Long – The firmware detects and reports to the coordinator a long click (2000 ms). The firmware also sends the release event when a button is unpressed.

Double – The firmware detects and reports a double click (max 500 ms between clicks).

Triple – The firmware detects and reports a triple-click (max 500 ms between clicks).

Switch – an input works as a switch. Only ON (pushed) / OFF (released) states. This option works if the input is linked to the corresponding output. When the switch changes a state, the firmware immediately reports a state of the output. The output can be virtual and assigned to any unused pin.

Switch is On & Link is Off – in this mode, the firmware reports click and release events for an input, also for fast clicks.

Toggle – this option appears for the switch input. The switch works like a toggle button. But because the ON/OFF state can be changed via external commands, a physical button position may differ from an output state.

Bind command – the device sends a click event as this Zigbee command to a bound device, if any. It does not change behavior of internal events and a linked output.

Note: Input 1, if defined as a click button, also acts as a system button and allows you to reset the device if you press and hold that button for 10 seconds. After resetting, the device starts a paring process.

Zigbee cluster: ZCL_CLUSTER_ID_GEN_MULTISTATE_INPUT_BASIC
Zigbee attribute: ATTRID_IOV_BASIC_PRESENT_VALUE
Data type: UINT8 (0 - button released, 1 - single click, 2 - double click, 3 - triple click, 4 - long press (more than 1500 ms))

External wake-up

This is the special GPIO input type. It does not send any button events to a coordinator, but it initiates an extra periodic report, when the device sends a state of all GPIO outputs and measured values from all sensors. Furthermore, if “External wake-up” is configured on Input #1, it works as a pairing button.

GPIO outputs

Inversed – By default, the firmware sets the output pin to HIGH when a logical state is ON. You may invert that logic using this option.

Remember state – The firmware saves the output state to NVRAM and restores it after power off/on. Furthermore, this option works for some sensors (counter, PWM)

Role – this options allows you to specify a role of the corresponding output. The configurator uses this option only when creates a custom converter for Z2M. As a result, the output may have a different icon and associated actions in a frontend or Home Assistant.

Zigbee cluster: ZCL_CLUSTER_ID_GEN_ON_OFF
Zigbee attribute: ATTRID_ON_OFF

Virtual pins

The firmware adds a set of virtual pins:

  • CC253x: from P30 to P37
  • CC2652, CC1352: from P40 to P47

These pins do not exist in the chip, but you may use them in your configuration. For example, when you need to link an input and a virtual output, add a group switch or signal level control.

Zigbee2MQTT commands

on/off – sets the output to the HIGH or LOW state.

Topic: zigbee2mqtt/[friedly_name]/[channel]/set
Channel: l1, l2, l3 … l16
Payload: ON or OFF

read – gets the current state of a GPIO output.

Topic: zigbee2mqtt/[friedly_name]/[channel]/get/state
Channel: l1, l2, l3 ... l16
Returns the channel state: {"state_[channel]": "ON"}

trigger – sets the output to the HIGH state for N milliseconds, then resets to LOW. Please note, in the PSM mode the rigger may work unexpectedly with long intervals because the chip will go to the sleep mode and stop checking the timer. If you use the “Poll for queued commands” expert option, the trigger interval may be a multiple of this interval.

Topic: zigbee2mqtt/[friedly_name]/[channel]/set
Channel: l1, l2, l3 … l16
Payload: {"trigger": 5000}

interval – sets the periodic reporting interval output to N seconds. This command can be sent to any configured channel, but it will change the interval for all channels at once. The value of 0 or 65535 disables periodic reports.

Topic: zigbee2mqtt/[friedly_name]/[channel]/set
Channel: l1, l2, l3 … l16
Payload: {"interval": 50}

Comments
Harvey Specter
Posted at 02:08 March 4, 2024
Gill
Reply
Author

Thank you for this project.

Could you clarify the meaning of input and output channels?
Can 8 inputs and 8 outputs be used independently?
What is the exact benefit in linking input and output?
Could for example input 8 be used for ADC measurement and output 8 to turn something on/off?

Thanks.

    Harvey Specter
    Posted at 10:50 March 11, 2024
    Owner
    Reply
    Author

    Yes, you can have 8 independent inputs and outputs in the Premium version (16 channels). ADC input cannot control an output directly. The firmware will send an ADC value to your home automation system, and it can send a command back to change an output state. Internal linking allows you to on/off outputs without connection to a home automation system (offline mode).

Harvey Specter
Posted at 15:45 January 3, 2024
Julian
Reply
Author

Hi! Thank you for sharing this tool.

I have been trying for a long time to create a simple firmware configuration to turn on/off a led from Home Assistant using ZHA on a CC2530.
I am able to create the configuration, flash properly and add the device to Home Assistant. I am using configurator version 1.9.0.11 (from 2023-12-12).
I specified a status led in P00 and my output led in P02. The status led works fine, but the output led, nothing happens when I switch on/off from Home Assistant. In both cases I simply connected a red led with a small resistor to ground. If I measure voltage on P02 it’s always something like -1.37v and it doesn’t change in on or off position.
The config is super simple, besides the status led, I only have an output defined as GPIO with external pull down and generic role. I also tried external pull-up, no change.
I’m using the ZHA quirk generated by the configurator, which I confirm it’s successfully loaded.

NOTE: the generated quirk has a small bug, the model info says “ptvo.info ” (note the spaces). I had to remove the spaces to get the quirk to load.

Any ideas what I could be doing wrong? Why is it possible that the output in P02 never changes?
Thanks,
Julian

    Harvey Specter
    Posted at 10:04 January 4, 2024
    Owner
    Reply
    Author

    Please post your issue on GitHub, add your schematic and a screenshot of your configuration.

Harvey Specter
Posted at 15:17 August 10, 2023
AP
Reply
Author

Additional information. My inputs are configured as SWITCH same as in your example https://ptvo.info/zigbee-configurable-firmware-features/diy-examples/diy-zigbee-motion-detection-sensor-pir/ except they are not inversed and not binded to the output

Harvey Specter
Posted at 14:54 August 10, 2023
AP
Reply
Author

Hello, thank you for your efforts! I have a question – how to configure digital input so system reports logic level of an input as follows: when input signal is low level, the logic input status is false, when input is high, the input status is true. No matter what I tried in PTVO configuration, the input logic gets changed on a transition of input from low to hi level, so when I set input to the high level, the input logic goes true momentarily, then goes to false regardless of input signal level

Harvey Specter
Posted at 19:33 July 24, 2023
Jorn
Reply
Author

Hi,
For my project, I’d like to report periodically all the states of various sensors with PSM mode. Most of it is already working perfectly, so thanks for this wonderful configurator.
However one of the sensors (“Battery is charging using solar”) is a boolean sensor, configured as GPIO switch linked to a virtual output. I want to report this output periodically only and not when the state is updated (to safe some battery). Is this possible with the software and could you help me how to configure this?
Thanks

    Harvey Specter
    Posted at 03:26 July 25, 2023
    Owner
    Reply
    Author

    The firmware always sends a state of all GPIO outputs (real and virtual) and all sensor values in periodic reports.

      Harvey Specter
      Posted at 05:33 July 25, 2023
      Jorn
      Reply
      Author

      Hi, I already get all periodic reports, that is working properly. I want to disable the immediate reports when a GPIO input changes, is this possible?

        Harvey Specter
        Posted at 11:50 July 25, 2023
        Owner
        Reply
        Author

        No, you cannot configure the firmware in that manner.

Harvey Specter
Posted at 07:24 June 25, 2023
Martin
Reply
Author

Hello
I tried to implement the example here https://ptvo.info/zigbee-configurable-firmware-features/diy-examples/diy-zigbee-motion-detection-sensor-pir/.

My configuration (CC2530, Firmware: 1.9.0.2) is:

Output 3:
P30, GPIO, Role: Generic

Input 3:
P00, GPIO, Pull-up, Link to out 3, Binding command: On/Off

However, when applying 3.3 V to pin 00, the virtual switch is not marked ON. Even if I use a “real” output (e.g. P01) there is no change of the switching state of P01.

What can be the reason for this?

    Harvey Specter
    Posted at 05:21 June 26, 2023
    Owner
    Reply
    Author

    If you use “Pull-up”, you should connect the pin to GND to get the ON state.

Harvey Specter
Posted at 06:01 March 29, 2023
ov1d1u
Reply
Author

I have a Non-Contact Liquid Level Sensor (XKC-Y25-V) which simply outputs a high level 3.3V-9V if it detects water or low level 0V if it doesn’t. How can I use this with your firmware? I tried with GPIO input but it looks to be designed to work with buttons, not sensors (it only updates action when state changes) and also as an ADC, but the voltage is being reported only once every X seconds (where X is the reporting interval).

Harvey Specter
Posted at 09:30 March 22, 2023
Flavien
Reply
Author

If I configure a GPIO input like this:
– Link: off
– Switch: off
– Long: on
– Double/Tripple: on

Is there a delay before a single click event is reported, in order to detect double/tripple clicks?

Now if I turn off double/tripple (but leave long=on), will that remove the delay and send single clicks instantly?

    Harvey Specter
    Posted at 03:25 March 23, 2023
    Owner
    Reply
    Author

    The firmware generates a release event only for long clicks. A single click executes immediately, only if others click types are disabled.

      Harvey Specter
      Posted at 09:04 March 23, 2023
      Flavien
      Reply
      Author

      Thanks for the clarification. So can you confirm my understanding is correct:

      1. I don’t need to set “switch=on” for a push-button like this that reports clicks but no state
      2. With PSM and “switch=off”, an external pulldown resistor is not required
      3. With “switch=off” and all click types disabled, the firmware reports when the button is first pressed down, but not when it is released
      4. With “long=on”, it does not report when the button is first pressed down, instead it reports when the button is released

      Is that correct?

        Harvey Specter
        Posted at 03:47 March 24, 2023
        Owner
        Reply
        Author

        1,2,3 – Yes, correct.
        4 – The firmware reports a click after 300 ms and release when a button will be released.

Harvey Specter
Posted at 23:55 January 16, 2023
saper_2
Reply
Author

The mode Link allow for remote control output too?
I am looking for behavior: if input goes ON then out switch ON, if input goes OFF then output goes OFF. If input is ON (out ON too), sending remote command to switch output OFF, output is switched OFF. Now to turn it back ON using input I have to: toggle input OFF->ON. And when input is OFF (output OFF too), I send command to turn output ON, output switch ON; then to switch it OFF using input I have to toggle input ON, then OFF and output turn now OFF too.
Something like for output to “follow input state”.

    Harvey Specter
    Posted at 04:18 January 17, 2023
    Owner
    Reply
    Author

    You can try the “Switch mode” for the input.

Harvey Specter
Posted at 09:27 November 26, 2022
Alex S.
Reply
Author

Hi, for my battery powered device based on a CC2530 I need 8 inputs, PSM and an external wake-up. Unfortunately it seems not possible to have an external wake-up without sacrificing one input pin. Right?

Harvey Specter
Posted at 06:47 August 17, 2022
Kamil
Reply
Author

Do you have any working version of PWM with step motor? I need to create just 360* rotation with slow speed. I can’t find any working example

    Harvey Specter
    Posted at 10:19 August 17, 2022
    Owner
    Reply
    Author

    Hello. The firmware has PWM outputs with a low frequency where you can control a duty circle. But I didn’t test with with motors.

Harvey Specter
Posted at 16:46 April 7, 2022
Shay
Reply
Author

can a single input GPIO be used to control 2 outputs?
for example – use P00 as an inputs 1 and 2 then link output 1 as GPIO and link output 2 as PWM

Also, can you do a capacitive (touch) button?

Harvey Specter
Posted at 21:41 April 2, 2022
RaNo
Reply
Author

This page says:

“read – sets the output to the HIGH or LOW state”

I guess this is wrong. Should say something about reading rather than setting. Please verify.

    Harvey Specter
    Posted at 06:03 April 3, 2022
    Owner
    Reply
    Author

    Yes, thank you! I’ve updated that paragraph.

Harvey Specter
Posted at 00:24 March 11, 2022
Alex
Reply
Author

There is anyway to change input/output name? I mean show MyCustomName instead L1 before to be paired.

    Harvey Specter
    Posted at 04:16 March 11, 2022
    Owner
    Reply
    Author

    No, you cannot change it because it is hard-coded in Z2M. You can create a custom converter and define a custom description by editing a converter JS file manually.

Harvey Specter
Posted at 12:22 September 5, 2021
saeid
Reply
Author

I think there is a small typo on the last line.
“…but it will change the interval for all changes at once. ” should probably be
” but it will change the interval for all channels at once. ”

changes->channels

Harvey Specter
Posted at 05:53 August 6, 2021
Shonn
Reply
Author

What is the difference of pull up or down in the OUTPUT mode?

    Harvey Specter
    Posted at 06:36 August 6, 2021
    Owner
    Reply
    Author

    It depends on your schematic. Usually, if the logical “ON” state sets the “HIGH” level on the output, you use “pull-up.”

Harvey Specter
Posted at 21:40 April 2, 2021
Stefan
Reply
Author

Hello,
I fail to report input status (with home assistant) , work only if it is linked to output (so twice input & output goes to on/off)
Is there something i mess ?
Best regards

    Harvey Specter
    Posted at 06:15 April 3, 2021
    Owner
    Reply
    Author

    Hello. Yes, you need to link an input to a virtual output (P3x) if you need periodic reports.

Harvey Specter
Posted at 21:13 February 13, 2021
António
Reply
Author

Hi, an output power state to On is possible?

    Harvey Specter
    Posted at 05:46 February 14, 2021
    Owner
    Reply
    Author

    Hi, Sorry, but I didn’t understand your question.

Harvey Specter
Posted at 10:14 February 11, 2021
Alex
Reply
Author

In the firmware configuration, I should select CC2530 under Board Type? As there is no CC2531 option.

This is a general question, is the Zigbee2MQTT journal the best way to receive the reports from the CC2531? I am very new to this.

    Harvey Specter
    Posted at 10:45 February 11, 2021
    Owner
    Reply
    Author

    Usually, it is “CC2530 without an external oscillator”. But it may depend on your board.

Harvey Specter
Posted at 13:46 February 10, 2021
Alex
Reply
Author

Hi! I have a few questions. Can I indeed use your configurable firmware to flash a hex file onto a CC2531?
Further, what is the easiest way to use your configurable software to make end devices which can be used to send wireless reports of voltage(s) on the 8 input pins? Perhaps using the reliable voltage source on the chip as a “reference voltage”?

    Harvey Specter
    Posted at 03:29 February 11, 2021
    Owner
    Reply
    Author

    Hi!

    My firmware also supports CC2531. You should configure 8 input pins as ADC pins. That’s all.

      Harvey Specter
      Posted at 10:01 March 29, 2021
      Alex
      Reply
      Author

      Hi, what is the software configuration I should use to send the output of the voltage regulator on my CC2531 chip to one of the GPIO pins? I want to use a GPIO pin as a voltage source.

        Harvey Specter
        Posted at 11:03 March 29, 2021
        Owner
        Reply
        Author

        In general, it is a simple GPIO output. You can use pins P10 or P11 for powering your sensors (max 20 ma). But these pins are not available on the IO connector.

Harvey Specter
Posted at 12:35 February 5, 2021
Marc
Reply
Author

Hi

I have a device with 8 Inputs and 8 Outputs. I need the inputs and outputs being independent of each other. But would still want the input state shown as ON/OFF instead of getting the action (pressed/released). Can this be done?

    Harvey Specter
    Posted at 08:53 February 6, 2021
    Owner
    Reply
    Author

    Hi. It is not possible.

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