This mode features an auto-increment function of the address during the data
transfers. The 6-byte command eeBstCfg defines the 28-bit start address and the
burst length (1 to 2
16
transfers).
The length of a single data unit is fixed to word. Hence a maximum of 256 KB can
be transferred in burst addressing mode.
5.2.3 LBus-I/F protocol
Since no address signals are available externally, the addresses for data accesses
are part of a dedicated command protocol, which prelude each data transfer and
are sent by the Host CPU. These commands contain also information concerning
the type and direction of an access as well as the number of bytes to be transfered.
The commands can have up to six byte length, followed by a specified number
of data bytes.
Five different commands are available to set the related data transfer modes.
Following table gives an overview of the commands.
Table 5-4 LBus-I/F commands overview
Command
Function
Shortcut
Size
Name
eeShortOffs
2 byte
Short address offset
Sets the upper 12 address bits for
short addressing mode
eeShort
2 byte
Short address access
defines the lower 12 bits in short
addressing mode and initiates data
transfer
eeLong
4 byte
Long address access
defines 28 address bits in long
addressing mode and initiates data
transfer
eeBstCfg
6 byte
Burst transfer
defines 28-bit start address, burst
length and initiates burst data transfer
eeNOP
1 byte
No operation
Performs no operation
Host CPU Interface
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