56F8335 datasheet(35/160 Pages) FREESCALE

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Program Map

56F8335 Technical Data, Rev. 1

Freescale Semiconductor

Preliminary

4.2 Program Map

The Program memory map is located in Table 4-4. The operating mode control bits (MA and MB) in the

Operating Mode Register (OMR) control the Program memory map. At reset, these bits are set as indicated

in Table 4-2.

EXT_BOOT = EMI_MODE = 0 and cannot be changed in the 56F8335 or 56F8135.

After reset, the OMR MA bit can be changed and will have an effect on the P-space memory map, as shown

in Table 4-3. Changing the OMR MB bit will have no effect.

Table 4-4 shows the memory map options of the 56F8335/56F8135. The two right columns cannot be

used, since the EMI pins are not provided in the package; therefore, only the Mode 0 column is relevant.

Note: Program RAM is NOT available on the 56F8135 device.

Table 4-2 OMR MB/MA Value at Reset1

1. Information in shaded areas not applicable to 56F8335/56F8135.

OMR MB =

Flash Secured

State2,3

2. This bit is only configured at reset. If the Flash secured state changes, this will not be reflected in MB until the next reset.

3. Changing MB in software will not affect Flash memory security.

OMR MA =

EXTBOOT Pin

Chip Operating Mode

Mode 0 – Internal Boot; EMI is configured to use 16 address lines; Flash

Memory is secured; external P-space is not allowed; the EOnCE is disabled

Not valid; cannot boot externally if the Flash is secured and will actually

configure to 00 state

Mode 0 – Internal Boot; EMI is configured to use 16 address lines

Mode 1 – External Boot; Flash Memory is not secured; EMI configuration is

determined by the state of the EMI_MODE pin

Table 4-3 Changing OMR MA Value During Normal Operation

OMR MA

Chip Operating Mode

Use internal P-space memory map configuration

1. Setting this bit can cause unpredictable results and is not recommended, since the EMI is not functional in this package.

Use external P-space memory map configuration – If MB = 0 at reset, changing this bit has no effect.

56F8335 Datasheet(PDF) 35 Page - Freescale Semiconductor, Inc