Altera RapidIO MegaCore Function - Manual (Page 75)

Chapter 4: Functional Description 4–29
Logical Layer Modules
August 2014 Altera Corporation RapidIO MegaCore Function
User Guide
Figure 4–13 shows the signal relationships for four write transfers on the Avalon-MM
slave interface.
Figure 4–14 shows the signal relationships for two read transfers on the Avalon-MM
interface.
Reads and writes on the Avalon-MM slave interface are converted to RapidIO
maintenance reads and writes. The following fields of a MAINTENANCE type packet are
assigned by the Maintenance module:
■ prio
■ tt
■ ftype is assigned a value of 4'b1000
■ dest_id
■ src_id
■ ttype is assigned a value of 4'b0000 for reads and a value of 4'b0001 for writes
■ rdsize/wrsize field is fixed at 4'b1000, because only 4-byte reads and writes are
supported
■ source_tid
■ hop_count
Figure 4–13. Write Transfers on the Avalon-MM Slave Interface
sysclk
mnt_s_chipselect
mnt_s_waitrequest
mnt_s_write
mnt_s_address
mnt_s_writedata
0x4 0x8 0xC 0x10
32’hACACACAC 32’h5C5C5C5C 32’hBEEFBEEF 32’hFACEFACE
Figure 4–14. Read Transfers on the Avalon-MM Slave Interface
mnt_s_chipselect
mnt_s_read
mnt_s_address
mnt_s_readdata
mnt_s_readerror
0x14 0x4C
system clock
mnt_s_readdatavalid
mnt_s_waitrequest