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MicroBlaze Processor Reference Guide
UG081 (v14.7)
Chapter 3:
MicroBlaze Signal Interface Description
Wait
The
Wait
signal is an input to the core and indicates that the current transfer has been accepted, but
not yet completed. It is sampled on the rising edge of the clock.
CE
The
CE
signal is an input to the core and indicates that the current transfer had a correctable error. It
is valid on the rising edge of the clock when Ready is high. For reads, this signal indicates that an
error has been corrected on the
Data_Read[0:31]
bus, and for byte and halfword writes it
indicates that the corresponding data word in local memory has been corrected before writing the
new data.
UE
The
UE
signal is an input to the core and indicates that the current transfer had an uncorrectable
error. It is valid on the rising edge of the clock when Ready is high. For reads, this signal indicates
that the value of the
Data_Read[0:31]
bus is erroneous, and for byte and halfword writes it
indicates that the corresponding data word in local memory was erroneous before writing the new
data.
Clk
All operations on the LMB are synchronous to the MicroBlaze core clock.
LMB Transactions
The following diagrams provide examples of LMB bus operations.
Generic Write Operations
Figure 3-2:
LMB Generic Write Operation, 0 Wait States
Clk
Addr
Byte_Enable
Data_Write
AS
Read_Strobe
Write_Strobe
Data_Read
Ready
Wait
CE
UE
A0
BE0
D0
Don’t Care