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UNI-DS3 Development System
MikroElektronika
page
9.0.
00&6'&RQQHFWRU
The MMC/SD connector is used to enable memory cards to be interfaced with the microcontroller. To enable communication between
memory card and microcontroller, it is necessary to adjust their voltage levels. Memory card is powered by the 3.3V power supply
voltage (VCC3) generated by the REG2 voltage regulator, whereas the microcontroller’s power supply voltage is 5V (VCC). In case
the MCU card is powered with 5V power supply voltage, it is necessary to remove jumpers J17, J18 and J19. As a result, resistors
start acting as a voltage dividers. In this case, such divider is used to lower the microcontroller’s power supply voltage from 5V to
3.3V. To enable communication between microcontroller and memory card, switches 4, 5 and 6 on the DIP switch SW4 should be
set to the ON position.
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: MMC/SD memory card
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: MMC/SD connector connection schematic
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: MMC/SD connector
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