Message Format - 4.0 English

Alveo Card Management Solution Subsystem Product Guide (PG348)

Document ID

PG348

Release Date

2024-05-30

Version

4.0 English

Each request message written to the mailbox contains a 32-bit header. Request messages also contain payload information depending on the function requested. Mailbox response payload is written to remaining words of the mailbox buffer. The format of the Header is defined in the following table.

Table 1. Message Header Format
Message Header [31:24]	Message Header [23:12]	Message Header [11:0]
Opcode	Reserved	Message Length (bytes)¹
This field is only used for certain messages and might be populated as part of the Host Request Message or CMS Response Message. Further details can be found in the mailbox feature subsections.