C12 Alerts #1: CUR/RES pointer swap

[git4dcc]

Affected Components

• Modules: C12
• Severity: Medium
• Likelihood: Low
• Affected uCodes: ≤ F0004

Issue Summary

• The Rx/Tx pointer swap must occur strictly at the start of a standard bus frame. Currently, a logic error causes the microcode to trigger this swap during "padding frames"—sporadic frames injected by the C10 bus master. For these specific frames, the pointer swap must be deferred until the beginning of the subsequent non-padding frame.
  
  

Potential Impact

• The premature pointer swap results in incomplete Railcom data being sent upstream. Consequently, PC software fails to validate the data and rejects the Railcom response as corrupt or malformed.

Resolution

• Fixed Firmware Version: F0005
• Dependency: None