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Flash Memory Array and Control
Freescale Semiconductor
12-21
PXR40 Microcontroller Reference Manual, Rev. 1
19–20
WWSC
Write Wait State Control - This field is used to control the number of wait-states to be added to the
best-case flash array access time for writes. The best-case flash array access time for writes is two cycles.
This field must be set to a value corresponding to the operating frequency of the flash. Higher operating
frequencies require non-zero settings for this field for proper flash operation. This field is set to 0b11 by
hardware reset.
00 No additional wait-states are added
01 One additional wait-state is added
10 Two additional wait-states are added
11 Three additional wait-states are added
21–23
RWSC
Read Wait State Control - This field is used to control the number of wait-states to be added to the
best-case flash array access time for reads. The best-case flash array access time for reads is one cycle.
This field must be set to a value corresponding to the operating frequency of the flash and the actual read
access time of the flash. Higher operating frequencies require non-zero settings for this field for proper
flash operation.
This field is set to 0b111 by hardware reset.
000 No additional wait-states are added
001 One additional wait-state is added
...
111 Seven additional wait-states are added
Note: The settings for APC and RWSC must be the same.
Note: Valid settings are specified in the product Data Sheet.
24
Reserved
25
DPFEN
Data Prefetch Enable - This field enables or disables prefetching initiated by a data read access. This field
is cleared by hardware reset.
0 No prefetching is triggered by a data read access
1 Prefetching may be triggered by any data read access
26
Reserved
27
IPFEN
Instruction Prefetch Enable - This bit enables or disables prefetching initiated by an instruction read
access. This field is cleared by hardware reset.
0 No prefetching is triggered by an instruction read access
1 Prefetching may be triggered by any instruction read access
28
Reserved
29–30
PFLIM
Flash Prefetch Limit - This field controls the prefetch algorithm used by the flash prefetch controller. This
field defines a limit on the maximum number of sequential prefetches which will be attempted between
buffer misses. In all situations when enabled, only a single prefetch is initiated on each buffer miss or hit.
This field is cleared by hardware reset.
00 No prefetching or buffering is performed.
01 The referenced line is prefetched on a buffer miss, i.e., prefetch on miss.
1x The referenced line is prefetched on a buffer miss, or the next sequential line is prefetched on a buffer
hit (if not already present), i.e., prefetch on miss or hit.
31
BFEN
Flash Line Read Buffers Enable - This bit enables or disables line read buffer hits. It is also used to
invalidate the buffers. This bit is cleared by hardware reset.
0 The line read buffers are disabled from satisfying read requests, and all buffer valid bits are cleared.
1 The line read buffers are enabled to satisfy read requests on hits. Buffer valid bits may be set when the
buffers are successfully filled.
Table 12-12. FLASH_BIUCR Field Descriptions
Содержание PXR4030
Страница 1: ...PXR40 Microcontroller Reference Manual Devices Supported PXR4030 PXR4040 PXR40RM Rev 1 06 2011...
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Страница 66: ...Memory Map PXR40 Microcontroller Reference Manual Rev 1 2 4 Freescale Semiconductor...
Страница 120: ...Signal Descriptions 3 54 Freescale Semiconductor PXR40 Microcontroller Reference Manual Rev 1...
Страница 158: ...Power Management Controller PMC 5 26 Freescale Semiconductor PXR40 Microcontroller Reference Manual Rev 1...
Страница 182: ...Frequency Modulated Phase Locked Loop FMPLL 6 24 Freescale Semiconductor PXR40 Microcontroller Reference Manual Rev 1...
Страница 278: ...System Integration Unit SIU 7 96 Freescale Semiconductor PXR40 Microcontroller Reference Manual Rev 1...
Страница 280: ...System Information Module PXR40 Microcontroller Reference Manual Rev 1 8 2 Freescale Semiconductor...
Страница 300: ...Boot Assist Module BAM 9 20 Freescale Semiconductor PXR40 Microcontroller Reference Manual Rev 1...
Страница 346: ...Interrupts and Interrupt Controller INTC 10 46 Freescale Semiconductor PXR40 Microcontroller Reference Manual Rev 1...
Страница 352: ...General Purpose Static RAM SRAM 11 6 Freescale Semiconductor PXR40 Microcontroller Reference Manual Rev 1...
Страница 432: ...Core e200z7 Overview PXR40 Microcontroller Reference Manual Rev 1 13 44 Freescale Semiconductor...
Страница 460: ...Peripheral Bridge PBRIDGE 15 16 Freescale Semiconductor PXR40 Microcontroller Reference Manual Rev 1...
Страница 478: ...Memory Protection Unit MPU 16 18 Freescale Semiconductor PXR40 Microcontroller Reference Manual Rev 1...
Страница 496: ...Error Correction Status Module ECSM 17 18 Freescale Semiconductor PXR40 Microcontroller Reference Manual Rev 1...
Страница 524: ...Periodic Interrupt Timer PIT_RTI 20 12 Freescale Semiconductor PXR40 Microcontroller Reference Manual Rev 1...
Страница 740: ...FlexRay Communication Controller FLEXRAY 22 156 Freescale Semiconductor PXR40 Microcontroller Reference Manual Rev 1...
Страница 860: ...FlexCAN Module 24 50 Freescale Semiconductor PXR40 Microcontroller Reference Manual Rev 1...
Страница 928: ...Deserial Serial Peripheral Interface DSPI 25 68 Freescale Semiconductor PXR40 Microcontroller Reference Manual Rev 1...
Страница 982: ...Enhanced Serial Communication Interface eSCI 26 54 Freescale Semiconductor PXR40 Microcontroller Reference Manual Rev 1...
Страница 1114: ...Enhanced Queued Analog to Digital Converter EQADC 27 132 Freescale Semiconductor PXR40 Microcontroller Reference Manual Rev 1...
Страница 1167: ...Decimation Filter Freescale Semiconductor 28 53 PXR40 Microcontroller Reference Manual Rev 1...
Страница 1168: ...Decimation Filter 28 54 Freescale Semiconductor PXR40 Microcontroller Reference Manual Rev 1...
Страница 1262: ...Enhanced Time Processing Unit eTPU2 29 94 Freescale Semiconductor PXR40 Microcontroller Reference Manual Rev 1...
Страница 1399: ...Nexus Development Interface NDI Freescale Semiconductor 31 83 PXR40 Microcontroller Reference Manual Rev 1...
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