PMA agent
Agent is used for connecting of all components (driver, monitor,…). Agent has his own configuration object which contains two parameters: active (when is up then agent is active in other way is passive) and interface which say name of the interface that is used. When agent is active then sequencer and driver are created amd connected to interface. When is passive then only monitor is created.
PMA interface
PMA (Physical Medium Attachment) bus is proprietary interface which is connected to tranascievers. Main task of this interface is took data from encoder, scramble them and send it to tranasciever. There could be two types of data (depends on header), control data or usable data. On this interface are encoded data from encoder, this data could have this formats:
IDLEthis format contains: first eight bits which define type of frame (typeIDLE) and others zeros which specify space between frames.STARTthis format contains: first eight bits which define type of frame (typeSTART) and others bytes are data bytes.DATAthis format contains only data bytes and don’t have type.TERMINATEthis format contains: eight bits which define type of frame (typeTERMINATE), position of type depends on amount of data which are sended with terminate. So there in the first place there are data bytes (amount depends on number of data valid bytes), then type and in last there are zeros (space between frames).
PMA bus description
PMA bus has these 5 ports which will be described below.
Generics
Name |
Type |
Default |
Description |
|---|---|---|---|
DATA_WIDTH |
natural |
32 |
Data word width in bits. |
Ports
Name |
Dir |
Dimension |
Description |
|---|---|---|---|
DATA |
IN |
DATA_WIDTH |
Encoded and scrambled data from PMA. |
DATA_VLD |
IN |
DATA_WIDTH |
Data valid |
HDR |
IN |
2 |
Header from PMA, valid states are 01 (control block) and 10 (data block). |
HDR_VLD |
IN |
1 |
Header valid, this port is valid once per two clocks. |
BLOCK_LOCK |
IN |
1 |
This port say that transmiting has started. |
PMA sequence item
Sequence item contains basic ports from interface. All signals which are in sequence item are randomized. There are three methods:
do_copyis used for copying of the transaction.do_compareis used for comparing data of two transactions.convert2stringis used for printing whole transaction.
PMA monitor
PMA monitor is used for monitoring of traffic. There is only easy monitor which write whole transaction to analysis port.
PMA driver
PMA driver is used for driving PMA transactions to interface.