410-361

1300 Henley Court Pullman, WA 99163 509.334.6306 www.digilentinc.com PmodSSD Reference Manual Revised May 24, 2016 This manual applies to the PmodSSD rev. A Overview The PmodSSD is a two-digit seven-segment display. Users can toggle through GPIO signals which digit is currently on at a rate of 50Hz or greater to achieve persistence-of-vision to give the effect of both digits being lit up simultaneously. Features include: Two-digit high brightness seven-segment display Easily view a counter or timer Common Cathode configuration Small PCB size for flexible designs 1.0 1.7 (2.5 cm 4.3 cm) Two 6-pin Pmod connectors with GPIO interfaces Follows Digilent Pmod Interface Specification Type 1 The PmodSSD. 1 Functional Description The PmodSSD utilizes a common cathode configuration to display a variety of LED segment combinations. The ten segment combinations corresponding to digits 0 - 9 are generally the most useful, although other custom combinations can also be created. 2 Interfacing with the Pmod The PmodSSD communicates with the host board via the GPIO protocol. A logic level high signal on a particular anode will light up that respective segment on whichever digit is currently enabled. Users are able to select a particular digit by driving the Digit Selection pin (C) to a logic high or low voltage. Copyright Digilent, Inc. All rights reserved. DOC#: 502-126 Page 1 of 2 Other product and company names mentioned may be trademarks of their respective owners. PmodSSD Reference Manual Because only one digit can be lit at a particular time, users that want to use both digits to display a particular value will need to alternately light up the two digits at least every 20 milliseconds (50 Hz). This will correlate to each digit being lit up for 10 milliseconds each before the other segment needs to be turned on. Higher refresh rates can be achieved by alternating which digit is currently powered at shorter time intervals. Header J1 Header J2 Pin Signal Description Pin Signal Description 1 AA Segment A 1 AE Segment E 2 AB Segment B 2 AF Segment F 3 AC Segment C 3 AG Segment G 4 AD Segment D 4 C Digit Selection pin 5 GND Power Supply Ground 5 GND Power Supply Ground 6 VCC Positive Power Supply 6 VCC Positive Power Supply Table 1. Pinout description table. 560 AA P1 AB P2 AC P3 AD P4 AA1 AA2 GND AB1 AB2 AC1 AC2 Vcc AD1 AD2 AE1 AE2 AF1 AF2 AE AG1 AG2 P1 AF P2 C1 C2 AG P3 C P4 GND GND Vcc Vcc Figure 1. Seven-segment display connection diagram. Any external power applied to the PmodSSD must be within 2.7V and 5.25V; however, it is recommended that Pmod is operated at 3.3V. 3 Physical Dimensions The pins on the pin header are spaced 100 mil apart. The PCB is 1 inch long on the sides parallel to the pins on the pin header and 1.7 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. J2 Connector J1 Connector