NXP Semiconductors MPC5606S - BAM Software Flow

Boot Assist Module (BAM)
MPC5606S Microcontroller Reference Manual, Rev. 7
Freescale Semiconductor 171
6.5.4.2 BAM software flow
Figure 6-4 shows the BAM logic flow.
Figure 6-4. BAM logic flow
The first action is to save the initial device configuration. In this way, it is possible to restore the initial
configuration after downloading the new code but before executing it. This allows the new code to execute
as the device is just coming out of reset.
The BMODE and ABD fields of the SSCM STATUS register (see Section 38.2.2.1, System Status Register
(STATUS)) indicate which boot has to be executed (see Table 6-5).
If BMODE field shows either a single-chip value (011) or the reserved values, the boot mode is not
considered valid and the BAM pushes the device into static mode.
In all other cases the code of the relative boot is called. Data is downloaded and saved into the proper
SRAM location.
BAM
entry
0xFFFF_C000
Save default
configuration
check boot
mode
boot mode
valid?
STATIC mode
restore
default
configuration
NO
download new code
and save it into
SRAM
YES
restore
default
configuration
execute new
code
Which boot mode is selected is verified
by reading the SSCM_STATUS
register (BMODE and ABD)