mcf51jf128 Freescale Semiconductor, Inc, mcf51jf128 Datasheet - Page 575

• Manufacturer Part Number: mcf51jf128
• Description: Mcf51jf128 Reference Manual
• Manufacturer: Freescale Semiconductor, Inc

24.4.8 Bus Errors
There are certain accesses to the Mini-FlexBus that cause the system bus to hang. It is
important to have a good access-error handler to manage these conditions.
The types of accesses that cause the access to terminate with a bus error are:
Freescale Semiconductor, Inc.
• CSCRn[AA] is cleared.
• The clock to the Mini-Flexbus module is disabled. Mini-FlexBus accesses cause an
• Attempted writes to space defined as write protected (CSMRn[WP] is set) are
• Mini-FlexBus access not hitting in either chip select region is terminated with an
• Mini-FlexBus access hitting in both chip select regions is terminated with an error
error termination on the bus and prohibit the access to the Mini-FlexBus.
terminated with an error response and the access is inhibited to the Mini-FlexBus.
error response and the access is inhibited to the Mini-FlexBus.
response and the access is inhibited to the Mini-FlexBus.
FB_CLK
FB_A[Y]
FB_D[X]
FB_RW
FB_TS
FB_ALE
FB_CSn
FB_OEn
FB_BE/BWEn
FB_TA
FB_TSIZ[1:0]
Figure 24-31. Read-Bus Cycle with CSCRn[EXTS] = 1 (One Wait State)
MCF51JF128 Reference Manual, Rev. 2, 03/2011
Address
Address
TSIZ
Preliminary
AA=1
AA=0
Data
AA=0
AA=1
Chapter 24 External Bus Interface (Mini-FlexBus)
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