
182
AT85C51SND3Bx
7632A–MP3–03/06
Card Unit
Enable Smartmedia or XD card management is enabled by setting SMCEN bit in SCFG1 regis-
ter as detailed in Section “Configuration Descriptor” where specific configuration must
also be set.
Card Detect Input As shown in Figure 82 the SMINS (SMC/XD Card Detect) input implements an internal
pull-up, in order to provide static high level when card is not present in the socket.
SMINS level is reported by SMCD bit
(1)
in NFSTA.
As soon as SMC is enabled, all level modifications on SMINS input from H to L or from L
to H (card insertion or removal) set SMCTI, the SM Card Toggle Interrupt flag in NFINT.
Note: 1. SMCD bit is not relevant until SMC management is enabled.
Figure 82. Card Detection Input Block Diagram
Bit
Number
Bit
Mnemonic
Description
7-0 0
Reserved
The value read from these bits is always 0.
3-2 SHERRID1-0
Second Half Error Id Flag
Id of the error in the second “256-byte” group of the sector.
1: Correctable error.
2: Not correctable error.
3: Not correctable error in the ECC. Anyway, the data is good.
1-0 FHERRID1-0
First Half Error Id Flag
Id of the error in the first “256-byte” group of the sector.
1: Correctable error.
2: Not correctable error.
3: Not correctable error in the ECC. Anyway, the data is good.
Table 201. ECC ERror Identification Byte
7 6 5 4 3 2 1 0
0 0 SHFB2 SHFB1 SHFB0 FHFB2 FHFB1 FHFB0
Bit
Number
Bit
Mnemonic
Description
7-6 -
Reserved
The value read from these bits is always 0.
5-3 SHFB2:0 Second Half Fail Bit Flag
2-0 FHFB2:0 First Half Fail Bit Flag
SMCTI
NFINT.4
SMINS
IOVDD
SMCD
NFSTA.7
R
PU
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