# v19.9.0

> This is a working draft for the up-coming 19.9.0 release.

We are pleased to announce the release of TT Zephyr Platforms firmware version 19.9.0 🥳🎉.

Major enhancements with this release include:

## What's Changed

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<!-- UL Telemetry -->
<!-- UL Debug / Developer Features -->
<!-- UL Drivers -->
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## Wormhole

### Power & Performance Improvements

  * Take Tensixes out of low power mode before taking DRAM out of low power (Tensixes are used during DRAM training in the resume phase)
  * Fix which DRAM instances get retrained when exiting DRAM low power
  * Put Tensix RISCs into reset while entering Tensix low power (CG) state
  * Only perform actions when power state changes for: Tensix, DRAM, PCIe
  * Disable PCIe low power mode for now, due to unresolved issues

### Fan control

  * Add `FAN_RPM` reporting in smbus telemetry and telemetry table
  * Fix `FAN_SPEED` telemetry to report target fan speed as a percentage
  * Add a force fan speed message (0x94)

### Ethernet

  * Update `ETH_LIVE_STATUS` telemetry to report link_status in the upper 16 bits (same as BH)
    * Updated for both smbus telemetry and telemetry table

## Blackhole

### New API

- Added [`TT_SMC_MSG_TOGGLE_SINGLE_TENSIX_RESET`](https://docs.tenstorrent.com/tt-system-firmware/doxygen/structtoggle__single__tensix__reset__rqst.html) ARC message to reset a specific Tensix tile (SYS-2832).

### Stability Improvements

- Updated Blackhole MRISC FW to v2.15
  - Tuned CA/WCK settings to address Galaxy revC data mismatch issues
- Fixed a bug with specific chips where the bootrom would get stuck on memory repair (postcode 0x13) (SYS-2903).

### Bug Fixes

- Fixed red LED not staying on for manufacturing test (SYS-3844).
- Fix for postcode 0x13 on p300 devices by triggering mem repair during DMC reset (SYS-3829).
- Fix for p300 recovery/preflash images not enumerating (SYS-3893).

## Grendel

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## Migration guide

An overview of required and recommended changes to make when migrating from the previous v19.8.0 release can be found in [19.9 Migration Guide](https://github.com/tenstorrent/tt-system-firmware/tree/main/doc/release/migration-guide-19.9.md).

## Full ChangeLog

The full ChangeLog from the previous v19.8.0 release can be found at the link below.

https://github.com/tenstorrent/tt-system-firmware/compare/v19.8.0...v19.9.0