# What can we improve in the hardware? **URL:** https://forums.maslowcnc.com/t/what-can-we-improve-in-the-hardware/22430 **Category:** Hardware **Created:** [October 2, 2024, 7:49pm UTC](https://forums.maslowcnc.com/t/what-can-we-improve-in-the-hardware/22430 "2024-10-02T19:49:43Z") **Posts on this page:** 1 **Showing post:** 157
### Author: ![AzaB2C](https://yyz1.discourse-cdn.com/flex031/user_avatar/forums.maslowcnc.com/azab2c/32/22286_2.png) [@AzaB2C](https://forums.maslowcnc.com/u/AzaB2C) #### Post date: [June 23, 2025, 3:00am UTC](https://forums.maslowcnc.com/t/what-can-we-improve-in-the-hardware/22430/157 "2025-06-23T03:00:14Z")
Are the TMC2209 ENN Pins unconnected and floating? If so, is that intentional because enable/disable happens via UART? Am wondering if this could be causing some boards to have one or both Z stepper motors unexpectedly/randomly not work. Am wondering if people with “bad boards” (that they would normally just trash) and unreliable Z axis behavior, but also have brilliant eyesight, dexterity and a fine tipped soldering iron… might see better behavior if they solder blob the TMC2209 ENN and GND pins, or jumper to one of the Aux GPIO pins that can be configured in firmware to toggle ENN? Have been looking at [https://github.com/MaslowCNC/Boards](https://github.com/MaslowCNC/Boards), asking because I’m used to seeing ENN pin driven by a GPIO, or, tied to GND to keep drivers always enabled. Sorry if this is a silly question, am relatively new to driving Stepper motors directly, [related chat](https://chatgpt.com/share/6858c2a6-b90c-800b-99bc-760639cb7e69). Am learning by digging around projects I like, and was curious about this observation. 4.0 and 4.1 schematics show TMC2209 pin 2 floating… ![image](https://canada1.discourse-cdn.com/flex031/uploads/maslowcnc/original/3X/b/d/bdd9e2f00488e3a2b03bc42eb8a0c0177cb22287.png) PCB shows pin 2 is not connected… ![image](https://canada1.discourse-cdn.com/flex031/uploads/maslowcnc/original/3X/a/0/a0ab8879702812c712506e28757bf07273130c60.png) TMC2209 DataSheet doesn’t mention any pull down resistor, so unconnected behavior is undefined? ![image](https://canada1.discourse-cdn.com/flex031/uploads/maslowcnc/original/3X/1/7/17223a7989eabee60fc118230e692fb101d648d8.png) I haven’t physically inspected a board (e.g. test resistance between Pin 2 ENN and Pin 3 GND), partly because of eyesight and dexterity needed to precisely probe continuity of those TMC2209 pins. I haven’t closely inspected the firmware to see if/which GPIO Pin toggles ENN pin. Maybe the schematic and PCB design snapshots from GitHub that I’m looking at are outdated? > [@bar](#): > > The second connector on the board breaks out the serial port on the ESP32 which should let us add a nearly infinite number of extra pins if we need them. I think that we might also be able to disable serial in software and use those pins as GPIO, but I haven’t tried that Neat! Curious if anyone explored this, maybe for a pendant with physical buttons/rotary? --- _[View the full topic](https://forums.maslowcnc.com/t/what-can-we-improve-in-the-hardware/22430)._