Boot Assist Module (BAM)MPC5566 Microcontroller Reference Manual, Rev. 216-14 Freescale SemiconductorUpon receiving a valid FlexCAN message with an ID equal to 0x0011 that contains eight data bytes, or avalid eSCI message, the BAM uses a serial boot submode: FlexCAN serial boot mode, or eSCI serial bootmode.In FlexCAN serial boot mode, the eSCI A signal RXDA reverts to GPIO input. All data is downloaded onthe FlexCAN bus and eSCI messages are ignored.In eSCI serial boot mode, the FlexCAN A signals CNRXA and CNTXA revert to GPIO inputs and theTXDA signal is configured as an output. All data is downloaded on the eSCI bus and FlexCAN messagesare ignored.16.3.2.3.3 Download Process for FlexCAN Serial Boot ModeThe download process contains the following steps:1. Download the 64-bit password.2. Download the start address, VLE flag, and the number of data bytes to download.3. Download the data.4. Execute the boot code from the start address.12 18 14400 300 K 18.616 24 19200 400 K 14.020 30 24000 500 K 11.2Table 16-9. FlexCAN and eSCI Reset Configuration for FlexCAN and eSCI BootPin Label ResetFunctionInitial SerialBoot ModeSerial Boot Mode after Receiving a ValidFlexCAN Message eSCI MessageCNTXA GPIO CNTXA CNTXA GPIOCNRXA GPIO CNRXA CNRXA GPIOTXDA GPIO GPIO GPIO TXDARXDA GPIO RXDA GPIO RXDATable 16-10. FlexCAN and eSCI Reset Pin ConfigurationPins I/O Weak Pullup State Hysteresis DriverConfiguration Slew Rate Input Buffer EnableCNTXA_TXDA Output Enabled Up — Push/pull Medium NCNRXA_RXDA Input Enabled Up Y — — —GPIO Input Enabled Up Y — — —Table 16-8. Serial Boot Mode—Baud Rate and Watchdog Summary (continued)Crystal Frequency(MHz)System ClockFrequency (MHz) SCI Baud Rate FlexCANBaud RateWatchdog TimeoutPeriod (seconds)
