UM10503 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2012. All rights reserved.User manual Rev. 1.3 — 6 July 2012 1185 of 1269NXP Semiconductors UM10503Chapter 46: LPC43xx flash programming/ISP and IAP46.7.15 Set active boot flash bank This command is only valid if two flash banks exist on the part and selects one of the twobanks for booting from flash. The command inserts a valid signature (seeSection 46.4.4.1) in the selected flash bank and invalidates the signature in the other flashbank. After a reset, the part will boot from the selected flash bank and apply any code readprotection (CRP) that is included in the flash image of the selected bank to the entire flash(bank A and bank B).The set active boot flash bank command is disabled with CRP levels 1, 2, and 3. Thismeans that the boot flash bank cannot be changed if CRP is enabled. If CRP is includedin the new flash image to be activated by this command, ensure that the flash imagecontent is executing as expected. Otherwise, the part may fail to boot after reset and, forCRP level 3, external boot or ISP may not be accessible to update the flash.Return Code CMD_SUCCESS | (Source and destination data are equal)COMPARE_ERROR | (Followed by the offset of first mismatch)COUNT_ERROR (Byte count is not a multiple of 4) |ADDR_ERROR |ADDR_NOT_MAPPED |PARAM_ERROR |Description This command is used to compare the memory contents at two locations. Thiscommand is blocked when any level of code read protection is enabled.Example "M 436207616 268435968 4" compares 4 bytes from the RAM address0x1000 0200 to the 4 bytes from the flash address 0x1A00 0000.Table 1040.ISP Compare commandCommand MTable 1041.ISP Set active boot flash bank commandCommand SInput Flash bank: Selects flash bank A or B for booting if the part supports more than onbank. (0 = flash bank A, 1 = flash bank B).Return Code INVALID_FLASH_UNIT |INVALID_SECTOR |COMPARE_ERROR |USER_CODE_CHECKSUM |DST_ADDR_ERROR |BUSY | ERROR_SETTING_ACTIVE_PARTITIONDescription This command is only valid if there are two flash banks. It is used to enable bootingfrom the indicated flash unit by inserting valid signature and invalidating the otherflash unit. This command will not work if zeros are found where a vector table isexpected.Remark: An invalid image in the selected flash unit can cause boot failure andeven a system lockup when CRP3 is set.Example “S 0 ” selects flash bank A
