BOM-DAT/diode-dat/Diode-Schottky-dat/Diode-Schottky-dat.md
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@@ -26,5 +26,12 @@ SS54 / SS56： 5A 电流，40V / 60V 耐压。封装更大（通常是 SMC），
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+普通硅二极管： 血液流过它要交大约 0.7V 的过路费。如果升压模块输出 5.0V，经过普通二极管后，ESP32 只能拿到 4.3V。虽然 ESP32 开发板上有 3.3V 降压芯片，但 4.3V 的输入电压已经比较勉强了，发热也会增加。
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+肖特基二极管： 它的特点是过路费极低，通常只有 0.2V 到 0.3V 左右。5.0V 经过它之后，ESP32 依然能拿到约 4.7V 到 4.8V 的优质电压，系统运行会非常稳定。
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## ref
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Chip-cn-dat/Espressif-dat/ESP32-S3-DAT/ESP32-S3-DAT.md
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@@ -75,10 +75,10 @@ The **ESP32-S3** includes a **USB Serial/JTAG Controller**, meaning:
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Make sure the native USB pins are used:
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-| Function | GPIO Pin |
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-|--------------|----------|
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-| USB D+ | GPIO19 |
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-| USB D− | GPIO20 |
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+| Function | GPIO Pin |
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+| -------- | -------- |
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+| USB D+ | GPIO19 |
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+| USB D− | GPIO20 |
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> ⚠️ These pins must not be remapped or disabled in software if using USB JTAG.
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![](2025-08-19-16-53-29.png)
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+## common issues
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+### Quad vs. Octal SPI
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+| Feature | Quad SPI (Standard) | Octal SPI (OPI) |
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+| :-------------- | :------------------ | :-------------------- |
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+| **Data Lines** | 4 ($D_0$–$D_3$) | 8 ($D_0$–$D_7$) |
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+| **GPIOs 33–37** | Often available | Reserved / Internal |
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+| **Performance** | Standard | High-speed throughput |
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+**Note:** If you are using a standard Quad SPI module (like the basic N4 or N8 models without the "R8" suffix), these pins might be physically broken out to the header, but it is still best practice to check the specific datasheet for your module variant to ensure they aren't tied to internal PSRAM.
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+However, GPIO 33–37 are reserved for the Octal SPI flash interface on many ESP32-S3 modules (e.g. ESP32-S3-WROOM-1 with OPI flash). This means GPIO 37 (LF_PIN) likely conflicts with the flash bus and cannot be used for servo output.
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+GPIO 38 (LR_PIN) should be fine on most ESP32-S3 modules.
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Tech-dat/robotic-dat/Quadruped-Locomotion-dat/Quadruped-Locomotion-dat.md
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@@ -22,6 +22,52 @@ This is the smoothest and fastest way to move. You move diagonal pairs in a "cir
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+Trot Gait
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+LR and RR are mirrored, and LF and RF are mirrored,
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+LR and LF are swing in the same direction, LF and RF are swing in the same direction,
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+but pair of LR + LF and pair of RR + RF are swing in opposite direction
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+1. The 2-Step Forward Sequence
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+Here is how your diagonal pairs should coordinate:
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+Step A (Diagonal Pair 1):
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+Front-Left & Rear-Right swing Forward.
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+(At the same time, the other two legs push Backward).
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+Step B (Diagonal Pair 2):
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+Front-Right & Left-Rear swing Forward.
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+(At the same time, the other two legs push Backward).
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+What happens if you "Pulse" them together?
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+If you want them to move together, you have to do a "Gait" (步态). A common way to move "together" is the Trot Gait:
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+Diagonal Pair A: Front Left and Rear Right move forward.
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+Diagonal Pair B: Front Right and Rear Left move forward.
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+By moving diagonals together, the robot stays balanced on a line, and you get a much faster, smoother walk than moving one leg at a time.
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---
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### 2. The "Crawl" (High Stability)
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* **Action:** Only one "foot" moves forward at a time while the other three stay on the ground.
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* **Benefit:** The Center of Mass (CoM) is always supported by a triangle of legs, making it nearly impossible to tip over.
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+The Walking Sequence (Crawl Gait)
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+The safest way to move is to move one leg at a time while the other three form a stable triangle on the ground.
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+The Pattern:
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+Rear Left (RL) moves forward (Lift and swing).
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+Front Left (FL) moves forward.
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+Rear Right (RR) moves forward.
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+Front Right (FR) moves forward.
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---
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-3. Mechanical Implementation Tips
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+1. Mechanical Implementation Tips
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| Foot Design | Benefit | Best For |