E a s y M x
P R O
v 7 a
U s e r M a n u a l
P A G E 27
Secure Digital
(SD) is a non-volatile
memory card format developed for use
in portable devices. It comes in different
packages and memory capacities. It is
mostly used for storing large amounts
of data. EasyMx PRO
v7a features the
microSD card slot
. The microSD form
factor is the smallest card format currently
available. It uses standard SPI user inter-
face with minimum additional electronics,
mainly used for stabilizing communication
lines which can be significantly distorted
at high transfer rates. Special ferrite is
also provided to compensate the voltage
and current glitch that can occur when
pushing-in and pushing-out microSD card
into the socket.
Enabling microSD
In order to access microSD card, you
must enable SPI communication
lines using
SW13.1
–
SW13.3
DIP
switches, as well as Chip Select (CS)
and Card Detect (CD) lines using
SW14.3
and
SW14.4
switches.
microSD card slot
FP2
FERRITE
E13
10uF
VCC-3.3V
VCC-MMC
C30
100nF
1
2
4
5
6
7
G
CS
Din
+3.3V
SCK
GND
Dout
CD
G
N
D
CN27
MICROSD
VCC-MMC
R52
10K
R51
10K
SD-CS#
PH_MISO
PH_MOSI
PH_SCK
SD-CD#
R56
27
m
ic
ro
S
D
C
A
R
D
S
LO
T
1
2
3
4
5
6
7
8
O
N
SW13
1
2
3
4
5
6
7
8
O
N
SW14
PH_MOSI
PH_MISO
PH_SCK
SD-CS#
SD-CD#
PD15
PD3
MCU_MOSI
MCU_SCK
MCU_MISO
DATA BUS
microSD card slot connection schematics
MUL
TIMEDIA