  In this paper, we describe a modular data acquisition system developed as the
foundation of a cosmic ray detector network. Each detector setup (henceforth
referred as a station) is composed of an independent hardware device that can
be controlled and read-out through the Internet. This device is designed to
acquire and process the signal of up to eight different detector planes. Each
of these detector planes uses plastic scintillator slabs that are optically
coupled to silicon photomultipliers (SiPM). Within a single station, different
geometries and plane orientations are possible using the same baseline design.
The main readout is based on a programmable system-on-a-chip (PSoC), a flexible
and re-configurable commodity hardware that is used to implement the trigger
and timing logic. A Time to Digital Converter (TDC) is used to determine the
precise timing of the event relative to a GPS timing signal and to estimate the
signal amplitude through the Time-over-Threshold (ToT) method. An auxiliary set
of sensors provide environmental information and station detector planes
orientation that, together with other operation data, are periodically sent to
a server using the MQTT protocol. Data is cached using an in-memory database
for online monitoring and further persisted into a SQL database for offline
analysis. The server framework is based in software application containers
allowing easy replication of the server infrastructure.
