Information

Table 28-35. Read 1s Block Command Error Handling
Error Condition Error Bit
Command not available in current mode/security FSTAT[ACCERR]
An invalid margin choice is specified FSTAT[ACCERR]
Program flash is selected and the address is out of program flash range FSTAT[ACCERR]
Data flash is selected and the address is out of data flash range FSTAT[ACCERR]
Data flash is selected with EEPROM enabled FSTAT[ACCERR]
Flash address is not longword aligned FSTAT[ACCERR]
Read-1s fails FSTAT[MGSTAT0]
28.4.11.2 Read 1s Section Command
The Read 1s Section command checks if a section of program flash or data flash memory
is erased to the specified read margin level. The Read 1s Section command defines the
starting address and the number of phrases or longwords to be verified.
Table 28-36. Read 1s Section Command FCCOB Requirements
FCCOB Number FCCOB Contents [7:0]
0 0x01 (RD1SEC)
1 Flash address [23:16] of the first longword to be verified
2 Flash address [15:8] of the first longword to be verified
3 Flash address [7:0]
1
of the first longword to be verified
4 Number of longwords to be verified [15:8]
5 Number of longwords to be verified [7:0]
6 Read-1 Margin Choice
1. Must be longword aligned (Flash address [1:0] = 00).
Upon clearing CCIF to launch the Read 1s Section command, the flash memory module
sets the read margin for 1s according to Table 28-37 and then reads all locations within
the specified section of flash memory. If the flash memory module fails to read all 1s (i.e.
the flash section is not erased), the FSTAT(MGSTAT0) bit is set. The CCIF flag sets
after the Read 1s Section operation completes.
Table 28-37. Margin Level Choices for Read 1s Section
Read Margin Choice Margin Level Description
0x00 Use the 'normal' read level for 1s
0x01 Apply the 'User' margin to the normal read-1 level
0x02 Apply the 'Factory' margin to the normal read-1 level
Flash Operation in Low-Power Modes
K20 Sub-Family Reference Manual, Rev. 2, Feb 2012
536 Freescale Semiconductor, Inc.