NXP Semiconductors K22F series, Reference Manual, Page: 621 / 1407

Address: 0h base + 28h offset = 28h
Bit 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
R
NUMSG 0 SGSIZE
W
Reset
* * * * * * * * 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 * * * * * * * *
* Notes:
NUMSG field: Device specific value •
SGSIZE field: Device specific value •
x_CR field descriptions
Field Description
31–24
NUMSG
Number of Segments Indicator
The NUMSG field indicates the number of equal-sized segments in the flash.
0x20 Flash is divided into 32 segments
0x40 Flash is divided into 64 segments
23–8
Reserved
This field is reserved.
This read-only field is reserved and always has the value 0.
SGSIZE Segment Size
The segment size is a fixed value calculated from the available flash size (rounded up to nearest power of
2) divided by 32 or 64, depending on the amount of available program flash. This field determines which
bits in the address are used to index into the
x _SACC and x _XACC bitmaps to get the appropriate
permission flags. The segment size is defined by the equation 2^(8 + SGSIZE[7:0]). The tables below
show a sampling of possible settings.
Flash Size Segment Size Segment Size Encoding
32 Segment Encodings
16 KBytes 16 KBytes/32 = 512 Bytes 0x1
32 KBytes 32 KBytes/32 = 1 KBytes 0x2
64 KBytes 64 KBytes/32 = 2 KBytes 0x3
128 KBytes 128 KBytes/32 = 4 KBytes 0x4
64 Segment Encodings
256 KBytes 256 KBytes/64 = 4 KBytes 0x4
512 KBytes 512 KBytes/64 = 8 KBytes 0x5
1 MBytes 1 MBytes/64 = 16 KBytes 0x6
2 MBytes 2 MBytes/64 = 32 KBytes 0x7
Chapter 28 Flash Memory Controller (FMC)
K22F Sub-Family Reference Manual, Rev. 4, 08/2016
NXP Semiconductors 621