410-086P Digilent

1300 Henley Court Pullman, WA 99163 509.334.6306 www.digilentinc.com PmodLS1 Reference Manual Revised May 26, 2016 This manual applies to the PmodLS1 rev. B Overview The Digilent PmodLS1 allows users to receive signals from multiple optical sensors, such as the popular combination of an IR LED with an IR sensor used in line-following robots. Features include: Infrared light detector with on-board sensitivity adjustment Interface with up to four reflective or transmissive photo detectors Works with Digilent IR Proximity Sensor Small PCB size for flexible designs 1.4 0.8 (3.6 cm 2.0 cm) 6-pin Pmod connector with GPIO interface Follows Digilent Pmod Interface Specification Type 1 The PmodLS1. 1 Functional Description The PmodLS1 is designed to be used with up to four sensors containing an infrared LED and an infrared-sensitive photo-transistor, such as the IR Proximity Sensor available from Digilent. When using Digilent s sensors, refer to the print on the board indicating the wire color for the correct orientation of the wire. If third-party sensors are used, refer to the board schematic available at www.digilentinc.com for the proper connection of the LED and photo-transistor. The module uses analog comparators to determine when the infrared detectors have sensed more infrared light than the threshold limit. The sensitivity of the sensors can be adjusted by adjusting the onboard potentiometer. 2 Interfacing with the Pmod The PmodLS1 communicates with the host board via the GPIO protocol. By the Pmod design, each of the outputs will only send a logic 1 value when its sensor is picking up more optical light than the threshold limit. When the Copyright Digilent, Inc. All rights reserved. DOC : 502-068 Page 1 of 2 Other product and company names mentioned may be trademarks of their respective owners. PmodLS1 Reference Manual light level is lower than the threshold limit, the output will instead send a logic 0 value. This style can then be connected to an interrupt within the system board for an ideal usage, although this is not necessary. Pin Number Description 1 Sensor S1 2 Sensor S2 3 Sensor S3 4 Sensor S4 5 Ground 6 VCC Table 1. Pin descriptions. Any external power applied to the PmodLS1 needs to be between 2.7V and 5.5V to ensure that no internal components on the Pmod are damaged. Digilent recommends operating this Pmod at 3.3V. 3 Physical Dimensions The pins on the pin header are spaced 100 mil apart. The PCB is 1.375 inches long on the sides parallel to the pins on the pin header and 0.8 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.