Use register lookup to find peripheral addresses, fields, access rules, and reset values for the selected MCU. Live values come from a separate debugger observation.
Look up a definition
If several devices or cores are present, name the one you mean. Search by purpose when you do not know the register name:
Verify the suggested register against the exact target before reading hardware.
Read the live state
- Resolve the register’s device, address, width, and access rules.
- If reset or programming would destroy evidence, use an existing debugger session or review the attachment precautions before requesting attach-only.
- Read the live value.
- Decode it using fields from the same device reference.
Some registers clear on read or use write-one-to-clear fields. Check the device reference before reading or modifying them. A generic read-modify-write can change unrelated flags.
Compare with firmware
Register diagnostics can identify inconsistencies with the available definitions. They do not establish that clocks, synchronization, or power sequencing are correct.
Troubleshoot
- No definitions available: verify the selected platform and reopen the project.
- Name is missing: search by function, then check the suggested device and register.
- Address disagrees with the manual: check the device, core, and revision before using it.
- A field is absent: consult the exact device reference rather than inventing a mask.
- Reset value differs from hardware: boot code, firmware, or debugger actions may already have changed it.
See GDB debugging for attachment and memory inspection. Last modified on September 12, 2026
