Aidan has described the physical connections and initial setup here : https://nodus.ligo.caltech.edu:30889/ATFWiki/doku.php?id=main:resources:computing:acromag#recovering_from_a_terminal_power_communication_outage .
Since I used a Raspberry Pi(domenica.martian) for communicating to Acromag(acroey.martian) card, I had to recompile everything for linux-arm architecture.
For EPICS installation, download the EPICS base from http://www.aps.anl.gov/epics/download/base/baseR22.214.171.124.tar.gz . Installing dependencies, build, install epics at /usr/local/epics. By downloading modbusApp source from https://llocds.ligo-la.caltech.edu/daq/software/source/epics-126.96.36.199_long-source.tar.gz , build the modbusApp for linux-arm architecture in modules/modbus directory inside epics base.
Put all the files mentioned by Aidan and run a tmux session to grab channels.
Also, pyModbus can be used to read the channels. I'll put the physical connections schematic shortly.