RabbitCore RCM3900 User’s Manual
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4.4.4 microSD Cards
The RCM3900 supports a removable microSD Card up to 1GB to store data and Web
pages. The microSD Card is particularly suitable for mass-storage applications, but is
generally unsuitable for direct program execution.
Unlike other flash devices, the microSD Card has some intelligence, which facilitates
working with it. You do not have to worry about erased pages. All microSD Cards sup-
port 512-byte reads and writes, and handle any necessary pre-erasing internally.
The microSD Card socket on the RCM3900 has a plastic insert when shipped to protect
the socket. This insert must be removed before you will be able to insert a microSD
Card.
Figure 10 shows how to insert or remove the microSD Card. The card is designed to fit
easily only one way — do not bend the card or force it into the slot. While you remove or
insert the 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 or other
contaminants off the contacts. You will sense a soft click once the card is completely
inserted. To remove it, gently press the card towards the middle of the RCM3900 — you
will sense a soft click and the card will be ready to be removed. Do not attempt to pull the
card from the socket before pressing it in — otherwise the ejection mechanism will get
damaged. The ejection mechanism is spring-loaded, and will partially eject the card when
used correctly.
Figure 10. Insertion/Removal of microSD Card
Rabbit recommends that you use the microSD Card holder at header J2 only for the
microSD Card since other devices are not supported. Be careful to remove and insert
the card as described, and be careful not to insert any foreign objects, which may short out
the contacts and lead to the destruction of your card.
U1
R1
R2
R15
C1
J1
U2
C2
R4
JP1
J2
R5
JP2 JP3 JP4 JP5
R3
Y1 C5
R7
R8
C7
C6
R11
U4
R9
U3
C3
R10
R6 C4
C8
C9 U5
C10
C11
C14
C15
C19
C18
R17
JP7
JP10
JP9
JP8
L1
J3
C22 C23
C27
C33
L2
C35
C12
C16
C20 C21
C24
C13
C17
C25
U6
C28
R18
C37
C29
Y2
R12
R13
R14
C31
C30
R16
C32
C26
C34
C36
R19
U7
R20
R21
C39
C38
R23
R24
R25 R26
1
C44
2
U8
C43
C49 C50
JP12
JP1
1
C41
C42
JP13
R27
Y3
R22
C40
JP14
C46
U9
C45
R29
R28
R30
Q1
R33
DS1
R34
R35
DS2
DS3
SPD
LNK ACT
FDX COL
BSY
CE
DS4
R32
RCM39XX
D1
U10
Q2
C47
C48
R31