#59 environment detector RTU

supervisor/session/rtu.lua

@@ -7,6 +7,7 @@ local util   = require("scada-common.util")
 -- supervisor rtu sessions (svrs)
 local svrs_boiler   = require("supervisor.session.rtu.boiler")
 local svrs_emachine = require("supervisor.session.rtu.emachine")
+local svrs_envd     = require("supervisor.session.rtu.envd")
 local svrs_redstone = require("supervisor.session.rtu.redstone")
 local svrs_turbine  = require("supervisor.session.rtu.turbine")
 
@@ -106,6 +107,7 @@ function rtu.new_session(id, in_queue, out_queue, advertisement)
             elseif u_type == RTU_UNIT_TYPES.SNA then
                 -- @todo Mekanism 10.1+
             elseif u_type == RTU_UNIT_TYPES.ENV_DETECTOR then
+                unit = svrs_envd.new(self.id, i, unit_advert, self.out_q)
             else
                 log.error(log_header .. "bad advertisement: encountered unsupported RTU type")
             end

supervisor/session/rtu/envd.lua

@@ -0,0 +1,100 @@
+local comms = require("scada-common.comms")
+local log   = require("scada-common.log")
+local types = require("scada-common.types")
+
+local unit_session = require("supervisor.session.rtu.unit_session")
+
+local envd = {}
+
+local RTU_UNIT_TYPES = comms.RTU_UNIT_TYPES
+local MODBUS_FCODE = types.MODBUS_FCODE
+
+local TXN_TYPES = {
+    RAD = 1
+}
+
+local TXN_TAGS = {
+    "envd.radiation"
+}
+
+local PERIODICS = {
+    RAD = 500
+}
+
+-- create a new environment detector rtu session runner
+---@param session_id integer
+---@param unit_id integer
+---@param advert rtu_advertisement
+---@param out_queue mqueue
+function envd.new(session_id, unit_id, advert, out_queue)
+    -- type check
+    if advert.type ~= RTU_UNIT_TYPES.ENV_DETECTOR then
+        log.error("attempt to instantiate envd RTU for type '" .. advert.type .. "'. this is a bug.")
+        return nil
+    end
+
+    local log_tag = "session.rtu(" .. session_id .. ").envd(" .. advert.index .. "): "
+
+    local self = {
+        session = unit_session.new(unit_id, advert, out_queue, log_tag, TXN_TAGS),
+        periodics = {
+            next_rad_req = 0
+        },
+        ---@class envd_session_db
+        db = {
+            radiation = {},
+            radiation_raw = 0
+        }
+    }
+
+    local public = self.session.get()
+
+    -- PRIVATE FUNCTIONS --
+
+    -- query the radiation readings of the device
+    local function _request_radiation()
+        -- read input registers 1 and 2 (start = 1, count = 2)
+        self.session.send_request(TXN_TYPES.RAD, MODBUS_FCODE.READ_INPUT_REGS, { 1, 2 })
+    end
+
+    -- PUBLIC FUNCTIONS --
+
+    -- handle a packet
+    ---@param m_pkt modbus_frame
+    function public.handle_packet(m_pkt)
+        local txn_type = self.session.try_resolve(m_pkt.txn_id)
+        if txn_type == false then
+            -- nothing to do
+        elseif txn_type == TXN_TYPES.RAD then
+            -- radiation status response
+            if m_pkt.length == 2 then
+                self.db.radiation = m_pkt.data[1]
+                self.db.radiation_raw = m_pkt.data[2]
+            else
+                log.debug(log_tag .. "MODBUS transaction reply length mismatch (envd.radiation)")
+            end
+        elseif txn_type == nil then
+            log.error(log_tag .. "unknown transaction reply")
+        else
+            log.error(log_tag .. "unknown transaction type " .. txn_type)
+        end
+    end
+
+    -- update this runner
+    ---@param time_now integer milliseconds
+    function public.update(time_now)
+        if not self.has_build and self.periodics.next_rad_req <= time_now then
+            _request_radiation()
+            self.periodics.next_rad_req = time_now + PERIODICS.RAD
+        end
+
+        self.session.post_update()
+    end
+
+    -- get the unit session database
+    function public.get_db() return self.db end
+
+    return public
+end
+
+return envd