PKP
VS1000 P
ROGRAMMER
’
S
G
UIDE
VSMPG
the ECC. ECC is calculated from the 16-bit values of dreg register.
The ECC generation uses the Hamming ECC principle. In case of 528 byte page nand
flash (small page) a 24 bit ECC is generated. This gives a performance of 2 bit de-
tection and 1 bit correction. For 2112 byte page nand flash memories (large page) the
calculation can be done in 512 byte sections.
17.3.3
Data register
NFLSH_DATA bits
Name
Bits
Description
dreg
15:0
Data read/write register. Can be used with or
without ECC.
All data transfers to/from the are done through this register. The operation of NFLSH_DATA
depends from dsp-ena-dbuf, dsp-rd-wrx and nf-rd-wrx. When dsp-rd-wrx is set the reg-
ister samples the data buffer (from pointer address dsp-dbuf-pntr) or the nand flash input
register (when dsp-ena-dbuf is low).
Data buffer reads/writes can be done in 16 consecutive clock cycles. It must be noted
that when the read mode (dsp-rd-wrd set) is selected it takes one clock cycle for the
control to transfer the first word from data buffer to dreg. Therefore it is recommended
that the read mode is set (+ ecc reset/enable/disable) as the nand flash operation is
started.
17.3.4
Interface control towards physical pins
NFLSH_NFIF bits
Name
Bits
Description
nf-byte-cnt
12:8
Rx / tx byte counter, hardware sends nf-byte-cnt
+ 1 bytes
nf-use-dbuf
7
write from buffer(1) or dreg register(0)
nf-dbuf-pntr
6:2
pointer address of the data buffer for next
read/write
nf-do-op
1
nand flash interface start operation bit (resets
when done)
nf-rd-wrx
0
read(1)/write(0) selection
NFIF control register can only be written in idle state. Current nand flash operation can
be terminated by setting the nf-sreset bit of the control register. When all bytes are
read/written an interrupt is given (if enabled)
Rev. 0.20
2011-10-04
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