Raspberry Pi 4 WiFi Fails When Setting HDMI to 2560×1440 Resolution

Raspberry Pi 4 WiFi Fail 2560x1440 Resolution

Enrico Zini was working on a digital signage solution based on Raspberry Pi 4, then he set the video output to 2560×1440, and all hell broke loose. And by that, I mean WiFi stopped working. It was not obvious at first but after a full day of debugging, trying both micro HDMI outputs, different HDMI cables, three different Raspberry Pi boards, different power adapters, Raspbian Buster and Buster Lite, different MicroSD cards… He could reproduce the problem in all conditions, all he needed to do was to set the resolution to 2560×1440, and WiFi would just stop working. Setting the resolution to 2048×1080 or lower, and all WiFi connectivity issues disappeared. He did not test at higher resolutions, and another user reported a similar problem happening at 2.4 GHz, but not at 5 GHz, albeit when setting HDMI output to 1920×1080. So it looks like interference, but as noted by some it’s also surprising because the HDMI port and the …

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Fix for Raspberry Pi 4 4GB model’s USB Ports not Working on Ubuntu 19.10

Raspberry Pi 4 4GB RAM Ubuntu 19.10

Ubuntu 19.10 server was recently released with official support for Raspberry Pi 4 SBC. Shortly after I read stories about the USB ports not working on the board, but it took another interesting turn as Canonical now explains the bug only affects RPI 4 with 4GB RAM, and USB works just fine on boards with just 1/2GB RAM. The issue has been identified and it’s been found to be a kernel bug with a solution in the works that being tested. In the meantime, you can access to your Raspberry Pi 4 4GB USB ports by limiting the memory to 3GB in /boot/firmware/usercfg.txt as follows: Alternatively here’s the link to an updated kernel provided by Hui Wang with you want to test it out: I built a testing kernel, not only includes the fix for USB host, but also includes all new patches from https://github.com/raspberrypi/linux.git rpi-5.3.y branch (about 107 patches). I tested both arm64 and armhf kernels on Pi4 without …

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ctxLink Open Hardware WiFi Debug Probe is based Black Magic Probe (Crowdfunding)


Last month, we wrote about Blip nRF52840 dev board that also included an STM32F103 MCU running the open source Black Magic Probe (BMP) firmware for debugging and programming. Based on the original Black Magic Probe hardware product page, BMP is a JTAG and SWD adapter used for programming and debugging ARM Cortex MCUs, and does not require intermediate programs such as OpenOCD or STLink server. Instead, you can run GNU Debugger (GDB) and select the virtual COM port offered by the debug board. The reason I’m bringing BMP again today, is because a new open source hardware wireless debugging probe for Cortex-M based on Black Magic Probe has been launched in the last few days. ctxLink key features and specifications: Microcontroller – STMicro STM32F401RE Arm Cortex -M4F MCU at up to 84 MHz Connectivity – 802.11b/g/n WiFi via Microchip WINC1500 module USB – 1x micro USB port for connection to host computer and/or power Debugging Features Implements SWD and JTAG …

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Embedded Linux Conference (ELC) Europe 2019 Schedule – October 28-30

Embedded Linux Conference Europe 2019 Schedule

I may have just written about Linaro Connect San Diego 2019 schedule, but there’s another interesting event that will also take place this fall: the Embedded Linux Conference Europe on  October 28 -30, 2019 in Lyon, France. The full schedule was also published by the Linux Foundation a few days ago, so I’ll create a virtual schedule to see what interesting topics will be addressed during the 3-day event. Monday, October 28 11:30 – 12:05 – Debian and Yocto Project-Based Long-Term Maintenance Approaches for Embedded Products by Kazuhiro Hayashi, Toshiba & Jan Kiszka, Siemens AG In industrial products, 10+ years maintenance is required, including security fixes, reproducible builds, and continuous system updates. Selecting appropriate base systems and tools is necessary for efficient product development. Debian has been applied to industrial products because of its stability, long-term supports, and powerful tools for packages development. The CIP Project, which provides scalable and customizable base image and BSP layers, is now used in …

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PhyWhisperer-USB Python Controlled USB 2.0 Sniffer Enables USB Security Testing (Crowdfunding)

PhyWhisperer-USB is a hardware USB sniffer & triggering platform that allows users to test the security of USB devices using side-channel power analysis and fault injection using a Python 3 interface, beside simply capturing packets. This has become especially important now as some USB devices include Bitcoin Wallets, FIDO2 keys, and encrypted drives with valuable data. PhyWhisperer-USB hardware specifications: FPGA – Xilinx Spartan 7S15 with 12,800 logic cells USB USB 2.0 Low/Full/High Speed mode PC connection – Micro-USB 2.0 HS port Host connection – Micro-USB port Target connection – USB-A female connector Trigger pattern – 1 – 64 bytes with mask Trigger delay – 0 – 1048576‬ cycles of 240 MHz internal clock derived from USB clock USB sniffer FIFO – 8192 bytes (FPGA block RAM, adjustable depending on FPGA utilization) Expansion – Spare digital I/O: 8 data pins, 1 clock pin routed to FPGA (on front panel) Clock output – 60 MHz Target Power Source – Selectable: Host USB …

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Linaro Connect San Diego 2019 Schedule – IoT, AI, Optimizations, Compilers and More

Linaro Connect San Diego 2019

Linaro has recently released the full schedule of Linaro Connect San Diego 2019 that will take place on  September 23-27. Even if you can’t attend, it’s always interested to check out the schedule to find out what interesting work is done on Arm Linux, Zephyr OS, and so on. So I’ve created my own virtual schedule with some of the most relevant and interesting sessions of the five-day event. Monday, September 23 14:00 – 14:25 – SAN19-101 Thermal Governors: How to pick the right one by Keerthy Jagadeesh, Software Engineer, Texas Instruments With higher Gigahertz and multiple cores packed in a SoC the need for thermal management for Arm based SoCs gets more and more critical. Thermal governors that define the policy for thermal management play a pivotal role in ensuring thermal safety of the device. Choosing the right one ensures the device performs optimally with in the thermal budget. In this presentation Keerthy Jagadeesh, co-maintainer of TI BANDGAP AND …

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STMicro Launches $10 STLINK-V3mini Mini Probe for STM32 MCUs


Last year, we reported STMicroelectronics launched STLink-V3 debugger & programmer for STM8 & STM32 microcontrollers that added I2C, SPI, and CAN interfaces compared the previous STLink-V2 model. It’s not particularly expensive either at $35, but if you ever wanted something more compact and cheaper, the company has now introduced STLink-V3mini debugger going for under $10. STLINK-V3Mini key features and specifications: JTAG / serial wire debugging (SWD) specific features: 3 V to 3.6 V application voltage support and 5 V tolerant inputs JTAG communication support SWD and serial wire viewer (SWV) communication support Virtual COM port (VCP) specific features: 3 V to 3.6 V application voltage support on the UART interface and 5 V tolerant inputs VCP frequency up to 15 MHz USB – Micro USB 2.0 connector for power and connection to host computer Misc – 2x color LEDs: communication, power; STDC14 signals protection Dimensions – 30 x 15 mm PCB The debugger & in-circuit programmer supports drag-and-drop Flash programming, …

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Fusion for TIVA v8 Development Board Enables Debugging & Programming over WiFi

Fusion for TIVA V8 Development Board

Texas Instruments TIVA Arm Cortex-M4 MCU family was first introduced in 2013, I tested a TIVA Launchpad the following years, and since microcontrollers have usually a long life span they are still in use today, and should still be available for many years. I’m writing about this TI MCU family today because MikroElektronika has just announced Fusion for TIVA V8 development board for TI TIVA, Stellaris and MSP432 microcontrollers with plenty of I/Os including some MikroBus expansion slots, as well as support for debugging and programming over WiFi in addition to the usual USB-UART interface. Fusion for TIVA v8 board specifications: MCU – Socket for MikroElektronika MCU CARD Display Interfaces 2x 20-pin TFT display connector 1x 16-pin LCD connector for 2×16 characters LCD displays in 4-bit mode,  optional PWM backlight driving feature Programming – On-board CODEGRIP programmer/debugger, JTAG connector for connecting an external programmer/debugger Connectivity – Ethernet port, WiFI in CODEGRIP programmer/debugger USB – 1x USB port, 1x USB-UART, Expansion …

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