ModalAI M0184 Gemini 915MHz ELRS
Table of contents
Summary
PROTOTYPE RELEASE
NOTE: THIS PRODUCT IS NOT INTENDED FOR PUBLIC USE AND IS A PROTOTYPE ONLY
Limitations:
- VOXL SDK 1.4.1+ is required
Transmitter Compatibility
In general, follow Express LRS guidance selecting 900MHz options.
VOXL SDK Support
SDK 1.4.1 or newer required. For VOXL SDK usage, please see voxl-elrs.
Dimensions
3D Drawings
TODO
2D Drawings
TODO
Features
| Feature | Details |
|---|---|
| Weight | TODO g |
| HxW | 33mm x 22mm |
| Frequency Bands | 915Mhz |
| Input Voltage | 5VDC |
| Serial Output | CRSF, 420k default |
| RF Chip | Dual SX1276 |
| Antenna | IPEX MHF |
| Firmware | ELRS 3.2 |
| MCU | 72MHz, 32-bit ARM M3 STM32F103C8T6 |
| Memory | 20Kb RAM |
| 64Kbit Flash | |
| Inputs | UART, push button |
| Outputs | QTY PWM, UART, R/G LED |
Hardware
Hardware Block Diagram
Connectors
Summary
BETA release: prototype hardware shown here with bluewire
| Connector | Description |
|---|---|
| J1 | Antenna 1 |
| J2 | Antenna 2 (not used in beta release) |
| J4 | PWM, RC UART |
| S1 | Bind button |
| D1 | Green LED |
| D2 | Red LED |
J4 - Header Solder Pads
| Pin | Name | Notes |
|---|---|---|
| 1 | GND | |
| 2 | P0 | PWM Channel 0, 3P3V |
| 3 | P1 | PWM Channel 1, 3P3V |
| 4 | P2 | PWM Channel 2, 3P3V |
| 5 | P3 | PWM Channel 3, 3P3V |
| 6 | GND | |
| 7 | TX | ELRS TX (to VOXL2), 3P3V, 420k CRSF |
| 8 | RX | ELRS RX (from VOXL2), 3P3V, 420k CRSF |
| 9 | 5V | Input Power, 5P0V |
| 10 | GND |
J1 - ANT1
Main RF path (915MHz).
J2 - ANT2
NOT USED IN BETA RELEASE
S1 - Bind button
Used to put receiver in bind mode.
D1 - Green LED
Solid when bound.
D2 - Red LED
Status LED, follows ELRS standards
Recommended Antennas
IPEX MHF + T antenna.
Programming Test Points
TODO
Software
Summary
| Component/Repo | Notes |
|---|---|
| elrs-build-docker | Docker container that can clone/build FW with ease |
| VOXL SDK | Used to deploy all required software/firmware components to VOXL / ELRS hardware |
| ExpressLRS_3.2.1 | Fork of Express LRS supporting ELRSv1 (goal is to mainline) that runs on ELRS v1 (M0184) |
| crsf_rc | PX4 driver running in voxl-px4 that communicates over CRSF to ELRS v1 hardware |
| voxl-elrs | VOXL2 command line utility, used to update FW/config on ELRS v1 from VOXL2, part of the SDK |
| FW bootloader | Closed source, shared with voxl2-io and VOXL ESC |
Software Block Diagram
User Guides
VOXL SDK
For VOXL SDK usage, please see voxl-elrs.
VOXL 2 Wiring Guide (M0054)
