1. ESP32 0.5ms tick

    You know that the maximal tick rate in ESP-IDF is 1000Hz.

    esp-idf menuconfig 1000Hz

    This is ok for almost applications and if you require sub-milli time precision, the extra timer or interrupt would be your friend. But why can't be 2000Hz tick rate set on 240Mz CPU? Here is a famous LED blinker …

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  2. ESP32 PHY board

    I'm making a simple esp32 board with ethernet. ESP32 has MAC and esp-idf supports PHYs like LAN87x0 and TLK110 already. Here is the schematic with KiCAD:

    esp32-tlk110 schematic

    I'll create a git repository for that hardware if it works.

    Update 2017-10-21

    Now it works!

    esp32-tlk110 works

    Revised KiCAD files for this board can be …

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  3. ESP32 GPIO output in deep sleep mode

    ESP32のGPIOをOUTPUT modeにしてバッファSN74LVC3G07を使ってRGBのLEDを点灯させていたのですがdeep sleep modeにしたときに全点灯してしまうことに気がつきました. まあこのシステムだとESP32が止まっても他に電力を食うものがあるので光ること自体はあまり問題ではないんですがちょっと格好悪いです.

    最初はdeep sleep modeに入る前に消しておいたらと思ったのですがdeep sleepするとGPIOがlowレベルになって全点灯してしまいました. いろいろやるうちに逃げ道を見つけることができました. いつま …

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  4. ESP32 SPI master issue

    esp-wroom-32 board

    My ESP-WROOM-32 board has 2 spi slave devices MPU-9250 and MS5611. I've troubled with DMA on spi. It looks issue 598 which happens when DMA is used with the half-duplex mode and the command/address phases are disabled. With enabling command phase, the problem went away.

    @@ -105,12 +105,12 …
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