SWRU543B January 2019 – June 2025 CC3230S , CC3230SF , CC3235MODS , CC3235MODSF , CC3235S , CC3235SF
A bit-band region maps each word in a bit-band alias region to a single bit in the bit-band region. In Arm® Cortex®-M4 architecture, the bit-band regions occupy the lowest 1MB of the SRAM. Accesses to the 32-MB SRAM alias region map to the 1-MB SRAM bit-band region, as shown in Table 2-5.
A word access to the SRAM or the peripheral bit-band alias region maps to a single bit in the SRAM or peripheral bit-band region.
A word access to a bit-band address results in a word access to the underlying memory, and similarly for halfword and byte accesses. This allows bit-band accesses to match the access requirements of the underlying peripheral.
The CC32xx family of Wi-Fi microcontrollers support up to 256KB of on-chip SRAM for code and data. The SRAM starts from address 0x2000 0000.
Bit-banding for peripherals is not supported in the CC32xx.
| Address Range | Memory Region | Instruction and Data Accesses | |
|---|---|---|---|
| Start | End | ||
| 0x2000.0000 | 0x2003.FFFF | SRAM bit-band region | Direct accesses to this memory range behave as SRAM memory accesses, but this region is also bit addressable through bit-band alias. |
| 0x2200.0000 | 0x23FF.FFFF | SRAM bit-band alias | Data accesses to this region are remapped to the bit band region. A write operation is performed as read-modify-write. Instruction accesses are not remapped. |