Differences

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--- 04_projects:03_rpi2040_pico_mmu [2025/08/21 18:21] – [Hardware BOM] jattie
+++ 04_projects:03_rpi2040_pico_mmu [2025/08/22 18:34] (current) – [Prototype and build controller board] jattie
@@ Line 306: / Line 306: @@
         }
     def decl_command(self, req):
-        if "prtouch" in req or "get_pres" in req or "get_steps" in req or "step_prtouch" in req:
+        #if "prtouch" in req or "get_pres" in req or "get_steps" in req or "step_prtouch" in req:
+        #    return
+        if any(key in req for key in ("prtouch", "get_pres", "get_steps", "step_prtouch")):
             return
         funcname, flags, msgname = req.split()[1:4]
@@ Line 388: / Line 390: @@
   * Acquire the hardware components
   * 3D print the Pico MMU Parts
+  * Prototype and build controller board
   * Assemble and configure the MMU
@@ Line 414: / Line 417: @@
 |[[https://www.aliexpress.com/item/1005003116653232.html?spm=a2g0o.productlist.main.37.12a95137SnMSUx&algo_pvid=ce7aa035-c7ba-4222-83da-663d0ab0b494&algo_exp_id=ce7aa035-c7ba-4222-83da-663d0ab0b494-36&pdp_ext_f=%7B%22order%22%3A%2298%22%2C%22eval%22%3A%221%22%7D&pdp_npi=6%40dis%21EUR%210.99%210.45%21%21%211.13%210.52%21%402103963717557784164415169e96c1%2112000024187507657%21sea%21IE%21173564001%21X%211%210%21n_tag%3A-29919%3Bd%3Aefff38b4%3Bm03_new_user%3A-29895&curPageLogUid=MXkdjCZE5OQL&utparam-url=scene%3Asearch%7Cquery_from%3A%7Cx_object_id%3A1005003116653232%7C_p_origin_prod%3A|Screw Countersunk M3 8mm]]|  1  |  :::  |  €1.44  |  50  |  €0.03  |
 |[[https://www.aliexpress.com/item/1005006790023154.html?spm=a2g0o.productlist.main.4.79cc6f59MNFWYK&aem_p4p_detail=202508210518141993610376785640003142268&algo_pvid=e694344a-c739-406d-928f-791eb2c7076d&algo_exp_id=e694344a-c739-406d-928f-791eb2c7076d-3&pdp_ext_f=%7B%22order%22%3A%222650%22%2C%22eval%22%3A%221%22%7D&pdp_npi=6%40dis%21EUR%211.72%211.10%21%21%2114.06%219.00%21%40211b80c217557786941211148e7a30%2112000038308083836%21sea%21IE%21173564001%21X%211%210%21n_tag%3A-29919%3Bd%3Aefff38b4%3Bm03_new_user%3A-29895&curPageLogUid=LrK92G3yhSkB&utparam-url=scene%3Asearch%7Cquery_from%3A%7Cx_object_id%3A1005006790023154%7C_p_origin_prod%3A&search_p4p_id=202508210518141993610376785640003142268_1|Screw Grub M3 6mm]] (optional)|  2  |{{:04_projects:mmu:screenshot_2025-08-21_134755.png?direct&50|}}|  €1.92  |  55  |  €0.04  |
-^TOTAL | | | | ^  €61.04  |
+^TOTAL ||||^  €61.04  |
+Based on the recent sandtable pico controller I anticipate to have similar controller costs that should land a populate board for €25.
+^MMU BOM Parts    |  €61  |
+^MMU Printed Parts|  €5  |
+^MMU Controller   |  €25  |
+^TOTAL            ^  €91  ^
+<WRAP center round info 60%>
+Based on an investment cost of €91, I think a DIY Pico MMU is worth the investment costs to get automated spool switching on my K1 Max.
+</WRAP>
+===== 3D print the Pico MMU Parts =====
+===== Prototype and build controller board =====
 Hardware not featured on the Pico MMU pages are the extras I intend to use for the project:
@@ Line 421: / Line 441: @@
   * Voltage Regulator/Buck Convertor
   * Connectors and Powersupplies
+==== How Servo Direction Works (ES3004 and Similar) ====
+  * The servo receives a PWM signal at 50 Hz (one pulse every 20 ms).
+  * The length of each pulse (in microseconds) tells the servo what angle to move to.
+  * Direction is determined by whether the pulse width is increasing or decreasing:
+  * Shorter pulse (e.g., 700 µs) → rotate counter-clockwise
+  * Longer pulse (e.g., 2300 µs) → rotate clockwise
+  * The servo does not rotate continuously—it moves to a position and holds it.
+==== Direction Is Relative to Neutral ====
+Neutral position is around 1500 µs
+From there:
+  * Decreasing pulse width → moves left (CCW)
+  * Increasing pulse width → moves right (CW)
+<WRAP center round tip 60%>
+So you're not telling it “go left” or “go right”—you're telling it “go to this position,” and the servo figures out the direction internally.
+</WRAP>
+===== Assemble and configure the MMU =====