= M-Link Data Layer =
M-link data layer operates with words of 4 bytes width.

== Data Frame Format ==

||<:tablewidth="90%">Sync||<:>Type||<:>Length||<:>Seq||<:>Dst||<:>Src||<width="20%":bgcolor="#b0b0b0">Data||<:>CRC||

||'''field'''||'''offset'''||'''size'''||'''description'''||
||Sync||0||2||Sync word. 0x2A, 0x50 = “*P”||
||Type||2||2||Frame type||
||Length||4||2||Frame length in 32-bit words. Valid length is 4 – 511 (data size 0-507)||
||Seq||6||2||Frame sequence number (counter)||
||Dst||8||2||Destination Address||
||Src||10||2||Source Address||
||Data||12||0-2028||Payload data. 0-507 32-bit words||
||CRC||last||4||CRC32||

Field offset and size in bytes.

Data flow: for each endpoint, SEND is what endpoint is sending

== Data Frame Types ==

||'''type'''||'''description'''||'''data format'''||
||0x0100||Run mode data||<:>application specific||
||0x0101||Register R/W request||<:|2>[[Frame_101_102]]||
||0x0102||Register R/W response||
||0x0103||Status response||<:>application specific||
||0x0105||RAM R/W request||<:|2>[[Frame_105_106]]||
||0x0106||RAM R/W response||
||0x0107||Configuration EEPROM R/W request||<:|2>[[Frame_107_108]]||
||0x0108||Configuration EEPROM R/W response||
||0x0110||FVME run mode data||[[VmeDaqRawdataFormat]]||
||0x0111||FVME request||<:|2>[[Frame_111_112]]||
||0x0112||FVME response||
||0x1001||JTAG single op request||<:|4>[[Frame 1001-1004]]||
||0x1002||JTAG single op reply||
||0x1003||JTAG shift 32 request||
||0x1004||JTAG shift 32 reply||
||0x5A5A||Loopback Test||<:>any data||
||0x5354||Stream data||<:>[[MStream]]||

== Reserved Addresses ==

||'''address'''||'''description'''||
||0xFEFE||point-to-point||
||0xFDFD||PCIe carrier board||

----
[[CategoryMlink|MLink]]