How bdring/midtbot_esp32 works
MidTBot ESP32 is an open-source pen plotter: an operator supplies G-code, the ESP32 running Grbl_ESP32 receives it over USB, Bluetooth, Wi-Fi, or from onboard SD, and the machine draws using its belt-driven X/Y motion and servo-lifted pen. The repository provides controller PCB designs, mechanical models, and sample G-code rather than the firmware source. The README documents the runtime relationships; the tree identifies design artifacts, so internal firmware wiring and finer hardware connections are not shown.
Main entry points: midtbot_esp32_assy.stp Pen plotter · midthead.gcode G-code input · README.md H-bot belt drive · V2 Controller PCB
Components 15
Plotter operation
- G-code input
Docs/samples/midthead.gcode - USB
- Bluetooth
- Wi-Fi
- Onboard SD
Controller electronics
- Grbl_ESP32
- ESP32 controller
- Controller PCB
PCB/V2
Motion and pen
- Stepper motors
- H-bot belt drive
README.md - Pen servo
- Pen plotter
STEP/midtbot_esp32_assy.stp
Design resources
- Printed parts
STL - Parts lists
PCB/BOM.md
Other components
- Operator
Connections 18
- Operator → G-code input: supplies
- Operator → USB: controls via
- Operator → Bluetooth: controls via
- Operator → Wi-Fi: controls via
- Operator → Onboard SD: uploads to
- G-code input → Grbl_ESP32: provides commands
- USB → Grbl_ESP32: carries commands
- Bluetooth → Grbl_ESP32: carries commands
- Wi-Fi → Grbl_ESP32: carries commands
- Onboard SD → Grbl_ESP32: provides files
- Grbl_ESP32 → ESP32 controller: runs on
- Grbl_ESP32 → Stepper motors: drives
- Grbl_ESP32 → Pen servo: controls
- Stepper motors → H-bot belt drive: move belt
- H-bot belt drive → Pen plotter: positions pen
- Pen servo → Pen plotter: lifts pen
- Printed parts → Pen plotter: form structure
- Controller PCB → ESP32 controller: hosts controller