Developing IoT Projects with ESP32 - Second Edition PDF

Hi everyone,
I’m studying ESP32 for an IoT project and I’m trying to find the book “Developing IoT Projects with ESP32 – Second Edition” in PDF format for learning purposes.
If someone can help or point me to a resource, I’d be very grateful.
Thank you!

https://redd.it/1pvpbn6
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Renesas e² studio / SSP install fails on macOS and Windows ARM VM (GetLastError 317)

I’m trying to develop and flash firmware for a Renesas Synergy DK-S7G2 board, but I’m completely blocked by tooling issues across macOS and Windows ARM (VM). For context I am using an M4 MacBook Pro

I want to confirm whether what I’m attempting is fundamentally unsupported, or if I’m missing a required step.

When I tried on the mac, it saud App fails to launch (“E2studio is damaged and can’t be opened”), also Synergy SSP is not available on macOS, so Synergy projects and flashing are unsupported even if e² studio runs.

Even on Windows 11 ARM VM (UTM / QEMU on Mac), Windows installs successfully, USB passthrough works, DK-S7G2 enumerates.

The LEDs on the board indicate power/debug connection

SSP v2.7.0 + e² studio installer fails with

InvocationTargetException
GetLastError() returned 317


The same error occurs when installing e² studio alone

Tried running as Administrator, changing install path, freeing disk space, reinstalling prerequisites, disabling firewall and still met with no success

https://redd.it/1pvq0pb
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Project Advice/MCU Selection for camera recording with overlay

Hi all,

For context I'm an embedded developer by profession, but this level of project is a bit out of my scope, I'm generally down in the bare-metal/FreeRTOS end of things, not the embedded linux end of the scale.

I have a project in mind that will take input from a single MIPI CSI (or USB, I don't really have a preference) camera, add some overlay graphics and text to the stream and save to SD card (or USB stick). Overlay graphics are generated from environmental sensors or incoming serial data (e.g NMEA GPS data). There is no requirement for video output, but it's a nice to have. Let's assume that 1080p quality is sufficient and I assume that encoding would be h.264 or h.265.

I'm assuming for now that the environmental sensors will mostly come "for free" in terms of MCU hardware and resources. Anything that can do the video heavy lifting will have enough to read a few SPI/I2C sensors and a UART or two.

I don't have a good handle on where to start for selecting an MCU. I can prototype this on a Pi, but I would be looking to integrate it onto a single PCB ideally. Maybe using the Raspberry Pi compute modules on a carrier are the way to go, but I would be open to a single PCB design either from scratch or based on a suitable open source design.

Any advice people can give around MCU selection would be helpful, especially with regard to:
- suitability for use with embedded linux (I'm assuming I would use yocto/buildroot to generate the OS).
- hardware support for video and associated software/kernel support
- existing open source designs


Thanks all and Merry Christmas!

https://redd.it/1pvq04l
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STM32H7B3I-DK and ESP32 s3 communication

Hello guys, I need some help. I want to build a UI with Square Line Studio on my STM32H7B3I-DK and communicate it with an ESP32-S3 N16R8. The STM32 will handle the GUI and read data from the ESP32 (where I will handle all the logic and states). The STM32 is only responsible for displaying the interface.

I have encountered some problems along the way. This is my first project on STM32, and I don’t really know how to, for example, enable SPI2 without breaking the whole Square Line Studio project. Any help or tips would be greatly appreciated.

https://redd.it/1pvps0r
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Reverse engineered 32-bit driver for USB Chief (USB sniffer)
https://redd.it/1pvtjdy
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Skills to develop during engineering course

Hello everyone,

As an electronics student who will graduate in 2028. What are the skills i should develop if my interest is around embedded and firmware side.
As ai is improving did it change any aspects of your job in this field.
Also do companies like NXP, intel, Qualcomm, bosch, TI conduct hackathons and internships related to this? If they do, what are the prerequisites to attend them. Also, what do interviewers like to see in cv and expect us to know and what should I be focusing on before I graduate?

https://redd.it/1pvv4ua
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Question about DDR3L DQS/DM byte lanes

Hi everyone, I came across this question when trying to route a board with DDR3L for the first time.

The DDR3L IC (MT41K256M16TW-107:P) has UDM/LDM, and UDQS/LDQS, and I am not sure whether to put the 'L' pins on byte lane 0, or byte lane 1.

To be more clear, by "byte lane 0", I refer to the byte lane that is connected to DQ[0:7\], and byte lane 1 refers to the one connected to DQ[8:15\].

I am seeing some conflicting information about what goes where.

This example puts LDM/LDQS to byte lane 0, https://github.com/fma23/XADC\_Zynq7000/blob/master/ZedBoard\_RevC.1\_Schematic.pdf

And this one does the opposite https://youtu.be/W3Jt\_y6PHjA?list=PLOWdivEsxi3s5c\_atSD8vQ8xYINmHR4Qm&t=249

And this one also does the opposite, the same as the phils lab video https://hforsten.com/img/pulsed/pulsed\_schematic.pdf


I would appreciate if someone could give some insight on why these different projects switch these pins, and whether it matters.

https://redd.it/1pvwdpm
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Advice for embedded role at seed stage startup

Hello! I recently finished my MS in ECE and have ~3 YoE in embedded systems (DSP, FPGA, bare-metal) at a defense contractor, plus a FAANG embedded internship from undergrad. My current role is stable but has felt a bit stagnant, so I’ve been window shopping for other jobs. Also looking for a pay bump and something exciting.

I recently interviewed with a seed-stage aerospace startup (orbital semiconductor manufacturing), and the process has gone very well. However the team is extremely small, only two full-time engineers (roughly similar experience to me) plus a few consultants.

What makes me excited: the high ownership and autonomy, roles across board bring-up/comms/and telemetry, code getting flight-tested almost monthly, strong founding team and potential long-term network.

What makes me worried: I’ve never worked on a team this small (and no way to “switch teams” if it gets bad), no established processes or senior engineers to lean on day-to-day, not sure how to think of comp packages.

For those who’ve made a similar jump (especially early-career engineers or hardware folks):
1. What do you wish you had evaluated more carefully before joining?
2. What questions should I ask founders that go beyond the usual “vision” stuff?
3. What compensation or equity terms tend to matter most in practice at this stage?
4. What were the biggest red flags you ignored early on and paid for later?
5. How did this kind of role impact your long-term career trajectory (positively or negatively)?

Thanks!

https://redd.it/1pvxl8h
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UWB For Local Positioning Recommendations

Can anyone recommend a brand of UWB chip for local positioning (<50m) they've had a good (or just OK) time using. <30cm accuracy is sufficient

https://redd.it/1pvyy1b
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Advice needed: Embedded Linux bringup on a custom PCB

Hello everyone,

Embedded software guy here but new to linux board bringup. I have a development kit that runs linux (Renesas RZ V2N) and we have the schematic as well as a working Yocto build for this board. How do we go about bringing up a custom PCB if we do not copy the reference schematic because it uses bigger/more expensive components?

For example, if we wish to use a 2GB DDR instead of the original 8 GB DDR on the EVK - from a software perspective, where do I make the change to support the new chip? Is it the second stage bootloader - the one after ROM code (ARM TF-A)? Where do I find the RAM initialisation and training code? What needs to change if let's say I choose a different emmc and NOR flash memories?
In short, what are the "gotchas" that might prevent my custom PCB with slightly different components than the reference design from booting into Linux ? I am working with a hardware guy too who will be handling the PCB work but I need to make sure that the I am able to patch SPL/uboot to make it work with the custom parts we choose.

https://redd.it/1pw09lz
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Flyback converter: Adding another secondary for MCU with primary-side (non-isolated) GND?

Hi everyone,

I’m working on a **400V → 12V flyback converter** using a custom transformer.

Current transformer windings:

* 1× Primary (HV side)
* 1× Auxiliary
* 1× Secondary (isolated) → used to generate **12V output**

Now I need **another low-voltage supply** to power an **MCU and some Relays**.
**Important constraint:**
The MCU **must share the same GND as the primary side (non-isolated)** because it needs to directly control components on the non-isolated side of the circuit.

My questions:

1. Can I **add an extra secondary winding** to the transformer and **reference it to the primary-side GND** to power the MCU and Relay?
2. If I do this, does that winding still count as a “secondary,” or is it effectively a **primary-referenced auxiliary winding**?
3. Are there **safety, EMI, or regulation issues** with having both:
* an **isolated secondary (12V output)**, and
* a **non-isolated low-voltage winding** (MCU supply) on the same flyback transformer?

Any reference designs, application notes, or practical advice would be really helpful.

Thanks in advance!

https://redd.it/1pw1c5i
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Any embedded engineers that got hired from asia to europe?

do they hire embedded engineers abroad in europe from asia,I have only ever seen software engineers get hired

Is it possible?

https://redd.it/1pw3x07
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STM32 Cube IDE I2C connection cannot be enabled

I greet the entire community.


I'm trying to use I2C, but as shown in the image, this part cannot be changed in any way. I can't figure out why. How can I fix this?




https://preview.redd.it/nli3ezquwj9g1.png?width=1638&format=png&auto=webp&s=20cf12554db078a664f041135bd7709ea866c25b



https://redd.it/1pw4ftl
@r_embedded

STM32 gotcha: disabling timer outputs (MOE=0) disables its internal outputs too

It is documented, but I still burned MOSFETs due to this, and it is not on the famous gotchas list. So I'm posting this :-) .

Some stm32 microcontrollers have OPAMPs that can have alternate inputs, configured by a timer PWM output. For instance, when TIM1 CH6 is low, the OPAMP looks at one pin. When CH6 is high, the OPAMP looks at another pin.

On the stm32g4, the OPAMPs can multiplex using either TIM1 CH6, TIM8 CH6 or TIM20 CH6. Some online documentation and application notes use TIM1 CH6 in their example.

Gotcha: If you ever disable the TIM1 outputs, for instance with LL_TIM_DisableAllOutputs(TIM1), the TIM1 PWM outputs become all low (expected), and TIM1 CH6 becomes stuck to low (unexpected!). So, this breaks the OPAMP multiplexing.

Workaround: Use TIM8 CH6 for multiplexing, or, if TIM8 may also be disabled, use TIM20 CH6 for OPAMP multiplexing. Ensure that LL_TIM_EnableAllOutputs(TIM20) is called.

By the way, does anyone know why the stm32 microcontrollers have so many gotchas? Or does a list like that exist for other families of microcontrollers too?

https://redd.it/1pw5frk
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Is it possible to make Emmc flasher like JTag or RTS5170 (I know its slower than JTag) using Raspberry Pico? Pico literally has 100Mhz and 2MB flash. I know it will be slow but still...?? I want to read Emmc of a android device using this and Jtag is too expensive...



https://redd.it/1pw3gdp
@r_embedded

Anyone else like algorithms, but hate writing drivers?

Hello all,

I like embedded systems and working close to hardware. I like seeing real things move, respond, and interact with the physical world.

What I don’t like is a lot of classic embedded like writing drivers and HAL, Board bring-up and vendor SDK glue.

The parts I enjoy are algorithm-heavy: Control systems, Signal processing.

Basically, I like embedded when the algorithm is the focus, not the plumbing. Are there roles that lean more this way, or need to focus on low level for jobs?


Thank you

https://redd.it/1pwer28
@r_embedded

Finding a sensor to create a Linux driver

Hi I am new to the world of embedded and Linux programming. I would like to create a Linux driver for a simple sensor like a temperature or pressure, using i2c. For the development I was thinking about doing that on my main computer using a i2c to USB converter. Only thing I would like to find a device that is well documented but no one has already built a Linux kernel driver on it, how can I find one?

https://redd.it/1pwffey
@r_embedded

Looking for internship

Umm I am in pretty much bad shape rn

I want an internship for next sixth months
frm 1st jan to 30th june

Preferred location: Pune(India)

- ECE student (final year) B.tech


https://redd.it/1pwe3kp
@r_embedded

Help with my CRC error

So i have an problem. I just wasted my day on this. So i have this SD Card module. It has a few Resistors and Capacitors. And the known pins. MISO MOSI SCK CS. I connected them on my ESP32 WROOM 32D. I did it correctly and i tried to initialize it. I was getting a CRC error and what not. Most if the time it was CRC. I tried to change the pins and got to the other SPI. Didn’t change a thing. I also added 10K resistors between chip pin and SD Module. Didn’t help. I have no idea what i can do. After a dew hours of troubleshooting i shorted the SD module😆(Ill get a new one tomorrow) but i do not know what to do.

https://redd.it/1pwj4eh
@r_embedded

Using an ESP32 to observe Bitcoin network behavior (no API) — looking for feedback

I built a small setup using an ESP32 to observe Bitcoin network activity directly, without relying on public APIs.

The goal is not price prediction, but understanding network stability, congestion patterns, and “is now a good time to send a transaction?”.

This is still experimental and hardware-driven.

I’d really appreciate feedback from people who have worked with ESP32, embedded monitoring, or Bitcoin nodes.

Happy to explain how it works if there’s interest.

https://redd.it/1pwe1nl
@r_embedded

How to start Embedded Linux as beginner?

Hi everyone,

I’m a computer science student and I’ve recently secured a 12-month firmware engineering internship starting next year. From what I’ve been told, the role will likely involve embedded Linux, Qt for embedded GUIs, and working mainly on Ubuntu/Linux environments.

I’m a total beginner when it comes to embedded Linux. I have programming experience (C/C++, Java, some C#), but I’ve never worked close to hardware or built a Linux system for embedded devices before.

I want to start preparing properly and avoid learning things in the wrong order.

I’d really appreciate guidance on:

• What foundational Linux skills I should learn first

• Whether I should start with desktop Linux (Ubuntu) or jump straight into embedded concepts

• Recommended learning path for embedded Linux (bootloaders, kernel, rootfs, device tree, etc.)

• When/how to introduce Qt for embedded Linux

• Any starter projects that make sense for a beginner

• Recommended hardware (e.g. Raspberry Pi, BeagleBone, or something else)

• Books, courses, or YouTube channels that are actually worth the time

My goal is to be productive from day one of the internship and build a solid long-term foundation in firmware/embedded systems.

Thanks in advance any advice from people working in embedded or firmware roles would be hugely appreciated 🙏

https://redd.it/1pwm5vi
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