1*34fd36daSMatthias Ringwald# BTstack Port with Cinnamon for Semtech SX1280 Controller on Miromico FMLR-80 2d42180bbSMatthias Ringwald 3d42180bbSMatthias Ringwald*Cinnamon* is BlueKitchen's minimal, yet robust Controller/Link Layer implementation for use with BTstack. 4d42180bbSMatthias Ringwald 5d42180bbSMatthias RingwaldIn contrast to common Link Layer implementations, our focus is on a robust and compact implementation for production use, 6d42180bbSMatthias Ringwaldwhere code size matters (e.g. current code size about 8 kB). 72fd737d3SMatthias Ringwald 82fd737d3SMatthias Ringwald## Overview 92fd737d3SMatthias Ringwald 102fd737d3SMatthias RingwaldThis port targets the Semtech SX1280 radio controller. The Host Stack and the Controller (incl. Link Layer) run on a STM32 MCU, with the SX1280 connected via SPI. 112fd737d3SMatthias Ringwald 12f508b9c4SMatthias RingwaldIt uses the SX1280 C-Driver from Semtech to communicate with the SX1280. The main modification was to the SPI driver that uses DMA for full packets. 132fd737d3SMatthias Ringwald 142fd737d3SMatthias Ringwald## Status 152fd737d3SMatthias Ringwald 166b8177c5SMatthias RingwaldTested with the [Miromico FMLR-80-P-STL4E module](https://miromico.ch/portfolio/fmlr-8x-x-stlx/) 176b8177c5SMatthias Ringwaldand our [SX1280 Shield](https://github.com/bluekitchen/sx1280-shield) - see (port/stm32-l476rg-nucleo-sx1280). 186b8177c5SMatthias RingwaldOn the FMLR-80-P-STL4E module, the 52 Mhz clock for the SX1280 is controlled by the MCU. 192fd737d3SMatthias Ringwald 20f508b9c4SMatthias RingwaldSEGGER RTT is used for debug output, so a Segger J-Link programmer is required. 212fd737d3SMatthias Ringwald 222fd737d3SMatthias RingwaldUses 32.768 kHz crytstal as LSE for timing 232fd737d3SMatthias Ringwald 24f508b9c4SMatthias RingwaldSupport for Broadcast and Peripheral roles. 252fd737d3SMatthias Ringwald 262fd737d3SMatthias RingwaldThe Makefile project compiles gatt_counter, gatt_streamer_server, hog_mouse and hog_keyboard examples. 272fd737d3SMatthias Ringwald 282fd737d3SMatthias Ringwald## Limitation 292fd737d3SMatthias Ringwald 302fd737d3SMatthias Ringwald### Advertising State: 312fd737d3SMatthias Ringwald- Only Connectable Advertising supported 322fd737d3SMatthias Ringwald- Only fixed public BD_ADDR of 33:33:33:33:33:33 is used 332fd737d3SMatthias Ringwald 342fd737d3SMatthias Ringwald### Connection State: 352fd737d3SMatthias Ringwald- Encryption not implemented 362fd737d3SMatthias Ringwald- Some LL PDUs not supported 372fd737d3SMatthias Ringwald 382fd737d3SMatthias Ringwald### Central Role: 392fd737d3SMatthias Ringwald- Not implemented 402fd737d3SMatthias Ringwald 412fd737d3SMatthias Ringwald### Observer Role: 422fd737d3SMatthias Ringwald- Not implemented 432fd737d3SMatthias Ringwald 442fd737d3SMatthias Ringwald### Low power mode - basically not implemented: 452fd737d3SMatthias Ringwald- MCU does not sleep 462fd737d3SMatthias Ringwald- SPI could be disabled during sleep 47f508b9c4SMatthias Ringwald- 1 ms SysTick is used for host stack although 16-bit tick time is provided by LPTIM1 based on 32768 Hz LSE. 482fd737d3SMatthias Ringwald 492fd737d3SMatthias Ringwald## Getting Started 502fd737d3SMatthias Ringwald 512fd737d3SMatthias RingwaldFor the FMLR-80-P-STL4E module, just run make. You can upload the EXAMPLE.elf file created in build folder, 522fd737d3SMatthias Ringwalde.g. with Ozone using the provided EXAMPLE.jdebug, and run it. 532fd737d3SMatthias Ringwald 542fd737d3SMatthias Ringwald## TODO 552fd737d3SMatthias Ringwald 562fd737d3SMatthias Ringwald### General 572fd737d3SMatthias Ringwald- indicate random address in advertising pdus 58f508b9c4SMatthias Ringwald- allow to set random BD_ADDR via HCI command and use in Advertisements 59f508b9c4SMatthias Ringwald- support other regular adv types 602fd737d3SMatthias Ringwald- handle Encryption 612fd737d3SMatthias Ringwald 622fd737d3SMatthias Ringwald## Low Power 632fd737d3SMatthias Ringwald- enter STANDY_RC mode when idle 642fd737d3SMatthias Ringwald- implement MCU sleep (if next wakeup isn't immediate) 652fd737d3SMatthias Ringwald- sleep after connection request until first packet from Central 662fd737d3SMatthias Ringwald- replace SysTick with tick counter based on LPTIM1 672fd737d3SMatthias Ringwald- disable SPI on MCU sleep 682fd737d3SMatthias Ringwald 69