1300 Henley Court Pullman, WA 99163 509.334.6306 www.digilentinc.com PmodSD Reference Manual Revised April 12, 2016 This manual applies to the PmodSD rev. B Overview The Digilent PmodSD allows system boards to read from and write to SD cards. With no limitation on the file system or memory size of the SD card, users will be able to store and access large amounts of data from their system board. Features include: Full size SD card slot Store and access large amounts of date from your system board No limitation on file system or memory size of SD card used 1-bit and 4-bit communication Small PCB size for flexible designs 1.8 1.8 (4.6 cm 4.6 cm) 12-pin Pmod port with SPI interface The PmodSD. 1 Functional Description The PmodSD is a great way to store and access information on a device that can then be accessed by outside devices such as a phone or computer. 1 Interfacing with the Pmod The PmodSD is designed to communicate with the host board primarily through the SPI protocol. By default, the SD card itself is defined to boot up in SD mode, but will enter into SPI mode when the Chip Select line is pulled low. The actual technique of writing to and reading from specific locations on an SD goes beyond the scope of this document, but the complexity of the process is nicely abstracted away within the chipKIT SD library. Copyright Digilent, Inc. All rights reserved. DOC : 502-123 Page 1 of 2 Other product and company names mentioned may be trademarks of their respective owners. PmodSD Reference Manual A pinout description table and diagram for the 2x6 pin header on the PmodSD can be found below: Pin Signal Description 1 ~CS Chip Select / Data3 2 MOSI MOSI / Command 3 MISO MISO / Data0 4 SCK Serial Clock 5 GND Power Supply Ground 6 VCC Power Supply (3.3V) 7 DAT1 Data1 8 DAT2 Data 2 9 CD Card Detect 10 WP Write Protect 11 GND Power Supply Ground 12 VCC Power Supply (3.3V) Table 1. Connector J1 pin descriptions. Any external power applied to the PmodSD must be within the specifications of the inserted SD card. As determined by the SD card association, this voltage range must be within 2.7 to 3.6 volts. The 3.3 operating voltage on Digilent system boards nicely complies with this standard. 3 Physical Dimensions The pins on the pin header are spaced 100 mil apart. The PCB is 1.8 inches long on the sides parallel to the pins on the pin header and 1.8 inches long on the sides perpendicular to the pin header. Copyright Digilent, Inc. All rights reserved. Page 2 of 2 Other product and company names mentioned may be trademarks of their respective owners.