Техническая Спецификация для Freescale Semiconductor Tower System Eval Kit for MC9S12GN32 TWR-S12GN32-KIT TWR-S12GN32-KIT

Freescale Semiconductor

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User margin levels can be used to check that Flash memory contents have
adequate margin for normal level read operations. If unexpected results are
encountered when checking Flash memory contents at user margin levels, a
potential loss of information has been detected.

The Set Field Margin Level command, valid in special modes only, causes the Memory Controller to set
the margin level specified for future read operations of the P-Flash or EEPROM block.

Upon clearing CCIF to launch the Set Field Margin Level command, the Memory Controller will set the

field margin level for the targeted block and then set the CCIF flag.

When the EEPROM block is targeted, the EEPROM field margin levels are
applied only to the EEPROM reads. However, when the P-Flash block is
targeted, the P-Flash field margin levels are applied to both P-Flash and
EEPROM reads. It is not possible to apply field margin levels to the P-Flash
block only.

Valid margin level settings for the Set Field Margin Level command are defined in

.

000

0x0E

Flash block selection code [1:0]

. See

001

Margin level setting.

0x0000

Return to Normal Level

0x0001

User Margin-1 Level

1

1

Read margin to the erased state

0x0002

User Margin-0 Level

2

2

Read margin to the programmed state

0x0003

Field Margin-1 Level

0x0004

Field Margin-0 Level