Microcontroller: Register Write Clear Effect Tool

Description

Parse current, writtenOnes, and clearableMask as width-bounded unsigned decimal integers.

A register mask selects bits within a fixed width. Read-clear and write-one-to-clear semantics describe state transitions that differ from ordinary assignment.

Parse current, writtenOnes, and clearableMask as width-bounded unsigned decimal integers.

When to use this tool

Use Microcontroller: Register Write Clear Effect when you need a deterministic fixed-width field or register-state calculation.

How to use the tool and how it works

Enter current, writtenOnes, clearableMask, width. Use the units and conventions below.
Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
Read result. Expand result to inspect the returned fields.

Parse current, writtenOnes, and clearableMask as width-bounded unsigned decimal integers. Clear only bits set in both writtenOnes and clearableMask; return next and the previously set bits that were cleared.^[1]

Input field	Meaning and units	Accepted input
current	Current	Required. Text. Implementation limit: 8192 Unicode code points and 16384 UTF-16 code units.
writtenOnes	Written Ones	Required. Text. Implementation limit: 8192 Unicode code points and 16384 UTF-16 code units.
clearableMask	Clearable Mask	Required. Text. Implementation limit: 8192 Unicode code points and 16384 UTF-16 code units.
width	Width	Required. Safe integer.

Output field	Interpretation	Returned shape
result	Result	Required. Object.
result.next	Next	Calculated result member: string.
result.clearedMask	Cleared Mask	Calculated result member: string.

json

{
  "input": {
    "current": "255",
    "writtenOnes": "15",
    "clearableMask": "5",
    "width": 8
  },
  "output": {
    "result": {
      "next": "250",
      "clearedMask": "5"
    }
  }
}

Limitations and assumptions

This models write-one-to-clear bits only; concurrent hardware changes and other register access semantics are omitted.
Outputs are nested inside result. Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.
Numeric calculations use binary floating point unless exact decimal-integer arithmetic is explicitly stated. No hidden measurement tolerance or decimal rounding is added; nonfinite or out-of-contract results are rejected. Numeric signed-zero results are exported as zero.

Alternative or Complementary methods

Use the device's access semantics and account for concurrent hardware changes before applying a register operation.

References

Calculation and input contract: microcontroller/register-write-clear-effect — tool.io