K60P100M100SF2RM Datasheet, PDF (740/1809 Pages) Freescale Semiconductor, Inc – K60 Sub-Family Reference Manual

Initialization/Application Information
The types of accesses that cause the access to terminate with a bus error are:
• Writes to write-protected region
• Address with no hit to any chip select
• Address with hits to multiple chip selects
• Writes to reserved addresses in the memory map
• Writes to reserved bits in the CSPMCR register
• FlexBus accesses when the FlexBus is secure
Also, the device can hang if the FlexBus is configured for external termination and the
CSPMCR is not configured for FB_TA.
29.5 Initialization/Application Information
29.5.1 Initializing a Chip Select
To initially use a chip select:
1. Configure the CSAR register.
2. Configure the CSCR register.
3. Configure the CSMR register, setting the valid bit.
The CSPMCR register is not required to be part of this procedure. However, it should
only be configured when the FlexBus is idle. The corresponding chip select can be valid.
29.5.2 Reconfiguring a Chip Select
To reconfigure a previously-used chip select, the chip select must be specified as invalid
as shown below:
1. Clear the CSMR register's valid bit.
2. Change settings in the CSAR register as necessary.
3. Change settings in the CSCR register as necessary.
4. Change settings in the CSMR register as necessary, and set the valid bit.
The CSPMCR register is not required to be part of this procedure. However, it should
only be altered when the FlexBus is idle. The corresponding chip select can be valid.
K60 Sub-Family Reference Manual, Rev. 6, Nov 2011
740
Freescale Semiconductor, Inc.