Introduction

The Baochip-1x is an SoC with enhanced open source and security features. Fabricated in TSMC22ULL, it has a 350MHz Vexriscv RV32-IMAC CPU with Sv39 (virtual memory) support, along with 2MiB of integrated SRAM and 4MiB of integrated RRAM. RRAM is non-volatile memory analogous to FLASH.

The full part number is BAO1X2S4F-WA, but the part is referred to as the “Baochip-1x” or the “bao1x” interchangeably.

This book is a work in progress.

Please join the Discord to request sections, or open a pull request to make edits and contributions. See RTL for where to find the source code for the chip.

The “Daric SDK” published by Cramium may also be of interest. This is the sister chip of the Baochip-1x. It has the exact same peripherals, but uses an ARM CPU. Most of the drivers and concepts apply across the two chips. This SDK is C-based, on top of ThreadX.

Potential Topics

Below is a list of potential topics for supplemental documentation. Note that many of the sections already have sample code in xous-core, and all the sections already have automatically-extracted documentation (Peripherals, CPU) with embedded links to the chip source code.

• clock generator
• PLL
• UDMA
  • UART
  • SPIM
  • I2C
  • SDIO
  • Camera
• Cryptoprocessors
  • SCERAM
  • Global setup
  • SDMA
  • Hash processor
  • PKE
  • AES
  • RNG
  • ALU
  • Sensors & countermeasures
• ATimer
• Always-on domain
• Power management & control
• RTC
• Keypad controller
• PWM
• Reset controller
• Interrupts/events
• CPU
• SRAM
• ReRAM
• watchdog timer
• DUART