Add sx127x component

[swoboda1337]

What does this implement/fix?

The SX127X component allows you to configure/control the SX1276, SX1277, SX1278 and SX1279 transceivers in ESPHome. Supported frequencies range from 137 MHz to 1020 MHz. Supported modulations include OOK, FSK, GFSK, MSK and GMSK. Support for both receive and transmit. These chips contain two modems. The LoRa modem is not supported by this component, only the FSK/OOK modem.

Datasheet: https://www.semtech.com/products/wireless-rf/lora-connect/sx1278#documentation

There are many devices in the market with an ESP32 already packaged with these radios, examples: https://www.lilygo.cc/en-ca/products/lora3, https://heltec.org/project/wifi-lora-32v2/ and https://shop.m5stack.com/products/m5stack-lora-module-433mhz-v1-1

There are already about a dozen or so people using my component. I currently use it for my 433 MHz AcuRite weather sensors (https://github.com/swoboda1337/acurite-esphome). It would be nice to get these radios officially supported.

Docs can be found here: https://deploy-preview-4278--esphome.netlify.app/components/sx127x

Types of changes

• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Other

Related issue or feature (if applicable): #7483

Pull request in esphome-docs with documentation (if applicable): esphome/esphome-docs#4278

Test Environment

• ESP32
• ESP32 IDF
• ESP8266
• RP2040
• BK72xx
• RTL87xx

Example entry for config.yaml:

Docs can be found here: https://deploy-preview-4278--esphome.netlify.app/components/sx127x

external_components:
  - source: github://pr#7490
    components: [ sx127x ]
    refresh: 5min
    
sx127x:
  nss_pin: GPIO18
  rst_pin: GPIO23
  frequency: 433920000
  modulation: OOK
  rx_start: true
  rx_bandwidth: 50_0kHz
  rx_floor: -90

remote_receiver:
  pin: GPIO32
  dump: raw

Checklist:

• The code change is tested and works locally.
• Tests have been added to verify that the new code works (under tests/ folder).

If user exposed functionality or configuration variables are added/changed:

• Documentation added/updated in esphome-docs.

[probot-esphome]

Hey there @swoboda1337,
Thanks for submitting this pull request! Can you add yourself as a codeowner for this integration? This way we can notify you if a bug report for this integration is reported.
In __init__.py of the integration, please add:

CODEOWNERS = ["@swoboda1337"]

And run script/build_codeowners.py

_{^{(message by NeedsCodeownersLabel)}}

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 53.81%. Comparing base (4d8b5ed) to head (49f71e8).
Report is 1571 commits behind head on dev.

Additional details and impacted files

@@            Coverage Diff             @@
##              dev    #7490      +/-   ##
==========================================
+ Coverage   53.70%   53.81%   +0.10%     
==========================================
  Files          50       50              
  Lines        9408     9795     +387     
  Branches     1654     1351     -303     
==========================================
+ Hits         5053     5271     +218     
- Misses       4056     4198     +142     
- Partials      299      326      +27     

☔ View full report in Codecov by Sentry.
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[lboue]

Build is OK for M5stack Cores3 and Module-LoRa868_V1.1.

[19:20:18][C][spi:064]: SPI bus:
[19:20:18][C][spi:065]:   CLK Pin: GPIO36
[19:20:18][C][spi:066]:   SDI Pin: GPIO35
[19:20:18][C][spi:067]:   SDO Pin: GPIO37
[19:20:18][C][spi:072]:   Using HW SPI: SPI
[19:20:18][C][sx127x:128]: SX127x:
[19:20:18][C][sx127x:129]:   NSS Pin: GPIO6
[19:20:18][C][sx127x:130]:   RST Pin: GPIO5
[19:20:18][C][sx127x:131]:   PA Pin: BOOST
[19:20:18][C][sx127x:132]:   PA Power: 17 dBm
[19:20:18][C][sx127x:133]:   Frequency: 869.524963 MHz
[19:20:18][C][sx127x:134]:   Modulation: OOK
[19:20:18][C][sx127x:135]:   Rx Bandwidth: 50.0 kHz
[19:20:18][C][sx127x:136]:   Rx Start: true
[19:20:18][C][sx127x:137]:   Rx Floor: -90.0 dBm
[19:20:18][C][sx127x:138]:   FSK Fdev: 5000 Hz
[19:20:18][C][sx127x:139]:   FSK Ramp: 40 us
[19:20:18][C][sx127x:147]:   FSK Shaping: NONE

[swoboda1337]

Converted to draft temporarily to do more fsk testing,

[herostrat]

No review, just a thank you for writing this component.
It works for me (heltec lora 32 v2)!

[swoboda1337]

Packet mode is done, works great with fsk there is an on_packet trigger. M5stack can be used now as it only supports packet mode. Need to add a few automations and it's done.

[swoboda1337]

Everything is done, will be updating the docs this week.

[paravoid]

Disclaimer: I know very little about the SX127s, so consider this a mostly uninformed review.

Broadly speaking, there are a lot of magic numbers in the code (some I've left comments at, but there are plenty more) and I had to go back and forth to the datasheet to unpack the code. So for clueless folks like me 😁, perahps it would be useful to add names to many (most?) of them, especially when the datasheet already has names defined for them (e.g. FXOSC).

Hope this review helps!

[swoboda1337]

Docs are done and I made some updates after review comments. Should be ready to go

[swoboda1337]

Moved to draft until new RMT drivers are integrated.