IFC: GPCM - burst length gives how many beats?

[ferdinandgrossm]

Hello,

I have another question regarding the GPCM mode of the LS1046A IFC.

In

21.3.7 Chip-Select Option register - GPCM (IFC_CSORn_GPCM)

it says for BURST_LEN:

GPCM burst length. It defines the maximum number of beats that will be sent/received in one burst cycle. This is programmed in terms of port-size transfer. For example, if the port size is 2 bytes and burst_length is 2, then the total of 8 bytes will be transferred in one burst cycle (that is, 4 beats of data transfers and each data transfer of 2 bytes).

Could someone please explain why a burst length of 2 results in 4 beats of data transfer?

Would I get only 2 beats if the port size were 1 Byte?

With the example given I could tranfer either 2 Bytes (no burst) or 8 Bytes (16, 32, ...). Is this somehow related to the internal architecture/bus width?

Thank you!

Regards

Ferdinand

[ferdinandgrossm]

Doh! Now I get it - "burst_length is 2" wasn't refering to the setting but the result...

Thanks for clearing that up!

[ufedor · Accepted solution]

The BURST_LEN wording seems to be unclear, but you just need to refer to the following table of the field values and corresponding beat numbers - i.e for the BURST_LEN=010 (2) the number of beats is 4.