NXP Semiconductors MC9S08QL4, Reference Manual

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Chapter 4 Memory
MC9S08QL8 MCU Series Reference Manual, Rev. 1
54 NXP Semiconductors
4.7.5 Flash Status Register (FSTAT)
Table 4-11. FPROT Register Field Descriptions
Field Description
7:1
FPS
Flash Protect Select Bits — When FPDIS = 0, this 7-bit field determines the ending address of unprotected
flash locations at the high address end of the flash. Protected flash locations cannot be erased or programmed.
0
FPDIS
Flash Protection Disable
0 Flash block specified by FPS7:FPS1 is block protected (program and erase not allowed).
1 No flash block is protected.
7 6 5 4 3 2 1 0
R
FCBEF
FCCF
FPVIOL FACCERR
0 FBLANK 0 0
W
Reset 1 1 0 0 0 0 0 0
= Unimplemented or Reserved
Figure 4-9. Flash Status Register (FSTAT)
Table 4-12. FSTAT Register Field Descriptions
Field Description
7
FCBEF
Flash Command Buffer Empty Flag — The FCBEF bit is used to launch commands. It also indicates that the
command buffer is empty so that a new command sequence can be executed when performing burst
programming. The FCBEF bit is cleared by writing a 1 to it or when a burst program command is transferred to
the array for programming. Only burst program commands can be buffered.
0 Command buffer is full (not ready for additional commands).
1 A new burst program command can be written to the command buffer.
6
FCCF
Flash Command Complete Flag — FCCF is set automatically when the command buffer is empty and no
command is being processed. FCCF is cleared automatically when a new command is started (by writing 1 to
FCBEF to register a command). Writing to FCCF has no meaning or effect.
0 Command in progress
1 All commands complete
5
FPVIOL
Protection Violation Flag — FPVIOL is set automatically when a command is written that attempts to erase or
program a location in a protected block (the erroneous command is ignored). FPVIOL is cleared by writing a 1
to FPVIOL.
0 No protection violation.
1 An attempt was made to erase or program a protected location.