Rabbit BL2600, User Manual

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User’s Manual 37
3.9.4 NAND Flash
The RCM3365 and the RCM3375 RabbitCore modules used with the additional BL2600
versions described in Section 1.2.2 support a removable memory card to store data and
Web pages. The RCM3365 and the RCM3375 both can handle up to a 128 MByte remov-
able memory card, and the RCM3365 also has a 16 MByte onboard NAND flash.
NOTE: Rabbit-based systems do not implement the xD-Picture Card ™ specification for
data storage, and are neither compatible nor compliant with xD-Picture Card ™ card
readers.
The NAND flash and removable memory cards are particularly suitable for mass-storage
applications, but are generally unsuitable for direct program execution. The NAND flash
differs from parallel NOR flash (the type of flash memory used to store program code on
Rabbit-based boards and RabbitCore modules currently in production) in two respects.
First, the NAND flash requires error-correcting code (ECC) for reliability. Although
NAND flash manufacturers do guarantee that block 0 will be error-free, most manufactur-
ers guarantee that a new NAND flash chip will be shipped with a relatively small percent-
age of errors, and will not develop more than some maximum number or percentage of
errors over its rated lifetime of up to 100,000 writes. Second, the standard NAND flash
addressing method multiplexes commands, data, and addresses on the same I/O pins,
while requiring that certain control lines must be held stable for the duration of the NAND
flash access. The software function calls provided by Rabbit for the NAND flash take care
of the data-integrity and reliability attributes.
Figure 22 shows how to insert or remove the memory card. While you remove or insert
the memory card, take care to avoid touching the electrical contacts on the bottom of the
card to prevent electrostatic discharge damage to the card and to keep any moisture and
contaminants off the contacts. Do
not remove or insert the memory card while it is being
accessed.
Figure 22. Insertion/Removal of Memory Card
R35
R36
R37
R38
C64 C75
U13
R75 R68 C74 C78
R65
R66
C77 R79
L1
J6
C26 C25
R45
C67
RP1
R12 J1
R1
1
R13 U5
R59
R60
R29
R61
C3
C2
R7U3
C9
C12 C13
C18
C21 C22
C65
C27
R25 C36
JP6
JP7JP8JP4JP5
Y2
R20 R21 C34
C58
C24
C19 C20
C15
C10
C11
R8
C6
C1
R10
Y1
R9
R2
C4
R5
C14
U2
C5 U1 R6
C28
R17
U4
R19
R18 R22
R23
R44
R31
R54
R53
C61
R81 R82
L2
J2
C71
C70
C80
C82
L3
C72
C76
C86
C79
RCM 3360/3370
R72
C81
R1
R14
R15
R26
R27 R76
R83
C35
C42
DS2
DS1
DS3
USR FM
LINK
ACT
C43
C29
R30
R24