diff --git a/supervisor/scada-supervisor.lua b/supervisor/scada-supervisor.lua
deleted file mode 100644
index 28a7e40..0000000
--- a/supervisor/scada-supervisor.lua
+++ /dev/null
@@ -1,55 +0,0 @@
---
--- Nuclear Generation Facility SCADA Supervisor
---
-
-os.loadAPI("scada-common/util.lua")
-os.loadAPI("scada-common/comms.lua")
-os.loadAPI("supervisor/config.lua")
-
-local SUPERVISOR_VERSION = "alpha-v0.1"
-
-local print_ts = util.print_ts
-
-local modem = peripheral.find("modem")
-
-print("| SCADA Supervisor - " .. SUPERVISOR_VERSION .. " |")
-
--- we need a modem
-if modem == nil then
-    print("No modem found, exiting...")
-    return
-end
-
--- determine active/backup mode
-local mode = comms.SCADA_SV_MODES.BACKUP
-if config.SYSTEM_TYPE == "active" then
-    mode = comms.SCADA_SV_MODES.ACTIVE
-end
-
--- start comms, open all channels
-if not modem.isOpen(config.SCADA_DEV_LISTEN) then
-    modem.open(config.SCADA_DEV_LISTEN)
-end
-if not modem.isOpen(config.SCADA_FO_CHANNEL) then
-    modem.open(config.SCADA_FO_CHANNEL)
-end
-if not modem.isOpen(config.SCADA_SV_CHANNEL) then
-    modem.open(config.SCADA_SV_CHANNEL)
-end
-
-local comms = comms.superv_comms(config.NUM_REACTORS, modem, config.SCADA_DEV_LISTEN, config.SCADA_FO_CHANNEL, config.SCADA_SV_CHANNEL)
-
--- base loop clock (4Hz, 5 ticks)
-local loop_tick = os.startTimer(0.25)
-
--- event loop
-while true do
-    local event, param1, param2, param3, param4, param5 = os.pullEvent()
-
-    -- handle event
-    if event == "timer" and param1 == loop_tick then
-        -- basic event tick, send keep-alives
-    elseif event == "modem_message" then
-        -- got a packet
-    end
-end
diff --git a/supervisor/startup.lua b/supervisor/startup.lua
index 2ee4d40..4ff56a9 100644
--- a/supervisor/startup.lua
+++ b/supervisor/startup.lua
@@ -1,3 +1,66 @@
 --
--- Multi-Reactor Controller Server & GUI
---
\ No newline at end of file
+-- Nuclear Generation Facility SCADA Supervisor
+--
+
+os.loadAPI("scada-common/log.lua")
+os.loadAPI("scada-common/util.lua")
+os.loadAPI("scada-common/ppm.lua")
+os.loadAPI("scada-common/comms.lua")
+
+os.loadAPI("supervisor/config.lua")
+os.loadAPI("supervisor/supervisor.lua")
+
+local SUPERVISOR_VERSION = "alpha-v0.1.0"
+
+local print_ts = util.print_ts
+
+ppm.mount_all()
+
+local modem = ppm.get_device("modem")
+
+print("| SCADA Supervisor - " .. SUPERVISOR_VERSION .. " |")
+
+-- we need a modem
+if modem == nil then
+    print("Please connect a modem.")
+    return
+end
+
+-- determine active/backup mode
+local mode = comms.SCADA_SV_MODES.BACKUP
+if config.SYSTEM_TYPE == "active" then
+    mode = comms.SCADA_SV_MODES.ACTIVE
+end
+
+-- start comms, open all channels
+if not modem.isOpen(config.SCADA_DEV_LISTEN) then
+    modem.open(config.SCADA_DEV_LISTEN)
+end
+if not modem.isOpen(config.SCADA_FO_CHANNEL) then
+    modem.open(config.SCADA_FO_CHANNEL)
+end
+if not modem.isOpen(config.SCADA_SV_CHANNEL) then
+    modem.open(config.SCADA_SV_CHANNEL)
+end
+
+local comms = supervisor.superv_comms(config.NUM_REACTORS, modem, config.SCADA_DEV_LISTEN, config.SCADA_FO_CHANNEL, config.SCADA_SV_CHANNEL)
+
+-- base loop clock (4Hz, 5 ticks)
+local loop_tick = os.startTimer(0.25)
+
+-- event loop
+while true do
+    local event, param1, param2, param3, param4, param5 = os.pullEventRaw()
+
+    -- handle event
+    if event == "timer" and param1 == loop_tick then
+        -- basic event tick, send keep-alives
+    elseif event == "modem_message" then
+        -- got a packet
+    elseif event == "terminate" then
+        -- safe exit
+        print_ts("[alert] terminated\n")
+        -- todo: attempt failover, alert hot backup
+        return
+    end
+end
diff --git a/supervisor/supervisor.lua b/supervisor/supervisor.lua
new file mode 100644
index 0000000..5f988a8
--- /dev/null
+++ b/supervisor/supervisor.lua
@@ -0,0 +1,15 @@
+-- #REQUIRES comms.lua
+
+-- supervisory controller communications
+function superv_comms(mode, num_reactors, modem, dev_listen, fo_channel, sv_channel)
+    local self = {
+        mode = mode,
+        seq_num = 0,
+        num_reactors = num_reactors,
+        modem = modem,
+        dev_listen = dev_listen,
+        fo_channel = fo_channel,
+        sv_channel = sv_channel,
+        reactor_struct_cache = nil
+    }
+end