Docs: Sound (DFPlayer)

Mon, 01 Jan 0001 00:00:00 +0000

DFPlayer Module

If your mainboard got delivered with an already equipped DFPlayer, you most likely got the original DFRobot-DFPlayer with a ‘DFRobot LISP3’ chip.

If you need to attach one, and your’re not located in the US, you might also use a DFPlayer-Clone with a ‘MH2024K-24SS’, ‘JL AB23A799755’ or ‘GD3200B’ chip, as sold by Amazon, AliExpress or the like.

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When using a DFPlayer-Clone,
in an open-mower-mainboard up to version 0.13.x,
you should cut-off Pin-11 from the DFPlayer-Clone:

If not, volume control will not work and always play at 100%!

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You also need to take attention that your motherboard has the required R7 and R13 (1k) resistors assembled:

Change DFPlayer’s V_CC to 5V

All mainboard version ≤ 0.13.x supply the DFPlayer with 3.3V by default. But for full sound support, it’s highly advised to change this to 5V, otherwise you might risk your Pico’s PMIC 💣. More technical details here: Sound-Readme

Don’t forget to cut the trace between middle and 3.3v! It’s there, even if it’s barely visible! (if you forgot, you’ll bridge the 3v3 with 5V resulting in incorrect battery voltage reporting)

Once changed, you’re save to enable full sound support via OM_DFP_IS_5V=True mower_config switch.

Sound SD-Card

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SDCard (128Mb) and DFPlayer Mini are included in the kit.

Take an SD card (different from the one you are using for RPi), format as FAT32, copy all MP3 files and folder to the root folder. Insert SD card to DFPlayer. Insert DFPlayer into motherboard SD card facing right (towards RPi)

☝️ Updated 11/2024

The soundfile structure completely changed in November 2024. If you already prepared your SD-Card before, it still works, but for full sound support you need to replace all files with the new structure (and take care that no old origin files remain on the SD-Card).

Speaker mount

There’re a couple of 3D-Printable speaker mounts available for different models. Worth to check OpenMower @ Printables

Docs: Troubleshoot Sound

Mon, 01 Jan 0001 00:00:00 +0000

All sounds get played infinite

This is most likely because your OpenMower’s mainboard miss R7 and/or R13. See DFPlayer Module.

But also happen if you use an old or damaged SD-Card which take loooong for getting the file allocation table.

Howto increase or decrease volume?

This depend on the type and version of your CoverUI:

Volume	Custom CoverUI Stock C500(A/B)	Alternate CoverUI	RM-ECOW-V1.0.0 (NX80i, …)	RM-EC3-V1.1 (NX100i)	SA/SC-Pro (240*160 Pixel)
up	`Mon`	`Sun`	`4H`	`1`	`↑`
down	`Tue`	`Mon`	`6H`	`2`	`↓`

I decreased my volume via volume-down button, but sound get still played at full volume

This is a known issue with DFPlayer-Clones in mainboard version 0.9.x up (and incl.) 0.13.x. Read here how to fix.

I do hear one or two more adverts as before, but no GPS-Pings, no “Bidaa bidaa” emergency, …

First off: “Bidaa bidaa” emergency signalling or similar, is an optional ‘background-sound’ feature, which is disabled by default. You need to enable it via export OM_BACKGROUND_SOUNDS=True in your mower_config.

If it still doesn’t play after changing export OM_BACKGROUND_SOUNDS=True in your mower_config, this is most likely because your DFPlayer’s SD-Card is still in the old format. See Sound SD-Card,

I do hear some new sounds, but they do not match to what happen

You mixed up DFPlayer’s SD-Card by adding the new files on top of the old ones. You need to remove all old files before copying the new ones. See Sound SD-Card.

Sound worked for a couple of weeks, but then my Pico suddenly died

This happen because you enabled full sound support by signalling it via OM_DFP_IS_5V=True flag, but didn’t switched it in real. See Change DFPlayer’s V_CC to 5V.

Don’t worry. A new Pico is cheap (~ 4$). Happy desoldering 😶!

OpenMower v1 Documentation – dfplayer