Atmel SpaceWire Router SpW-10X - Manual (Page 57)

Ref.: UoD_SpW-10X_
UserManual
Issue: 3.4
SpW-10X
SpaceWire Router
User Manual Date: 11 th
July 2008
Preliminary
57
Table 7-5 Read Single Address Characteristics
Action Supported/
Not Supported
Maximum number
of bytes Non-aligned access
accepted
8-bit read NS - -
16-bit read NS - -
32-bit read S 4 No
64-bit read NS - -
Word or byte address 32-bit aligned
Accepted Logical Addresses 0xFE
Accepted destination keys 0x20 at power on.
Accepted address ranges 0x00 0000 0000 – 0x00 0000 0109
Address Incrementation No
The RMAP read single address command is supported in the SpaceWire router. The single address
command is used to read a single 32 bit register location from the router registers.
In Figure 7-3 the format of a read single address command is illustrated. The first byte received by the
SpaceWire router configuration logic is the port address followed by the destination logical address.
Fields which are depicted in bold text are expected values. Fields which are shaded are optional.
Read Address (MS)
00h
Read Address
00h
Read Address Read Address (LS)
Data Length (MS)
00h
Data Length
00h
Data Length (LS)
04h
Header CRC
Config Port Address
00h
EOP
Last Byte Received
Destination Logical Address
FEh
Protocol Identifier
01h
Packet Type, Command
Source Path Addr Len
Destination Key
Source Path Address Source Path Address Source Path Address Source Path Address
Source Logical Address Transaction Identifier (MS) Transaction Identifier (LS)
Extended Read Address
00h
0 0 1 0 1 0
Bits in Packet Type / Command / Source Path Address Length Byte
MSB
Packet Type Command
Source Path
Address Length
Source Path
Address Length
LSB
Source Path Address Length
First Byte Received
Figure 7-3 Read Single Address Command Format