diff --git a/docs/lua-modules/ds18b20.md b/docs/lua-modules/ds18b20.md index 61fa8eb6..a9d1da54 100644 --- a/docs/lua-modules/ds18b20.md +++ b/docs/lua-modules/ds18b20.md @@ -5,8 +5,9 @@ This Lua module provides access to [DS18B20](https://datasheets.maximintegrated.com/en/ds/DS18B20.pdf) 1-Wire digital thermometer. -!!! note - The module requires `ow` C module built into firmware. +For integer version of firmware use [ds18b20-integer.lua](../../lua_modules/ds18b20/ds18b20-integer.lua) module - measured temperatures are multiplied by 10000. + +The module requires `ow` C module built into firmware. ### Require ```lua diff --git a/lua_modules/ds18b20/ds18b20-integer.lua b/lua_modules/ds18b20/ds18b20-integer.lua new file mode 100644 index 00000000..7e40a84b --- /dev/null +++ b/lua_modules/ds18b20/ds18b20-integer.lua @@ -0,0 +1,209 @@ +-------------------------------------------------------------------------------- +-- DS18B20 one wire module for NODEMCU +-- NODEMCU TEAM +-- LICENCE: http://opensource.org/licenses/MIT +-- @voborsky, @devsaurus, TerryE 26 Mar 2017 +-------------------------------------------------------------------------------- +local modname = ... + +-- Used modules and functions +local type, tostring, pcall, ipairs = + type, tostring, pcall, ipairs +-- Local functions +local ow_setup, ow_search, ow_select, ow_read, ow_read_bytes, ow_write, ow_crc8, + ow_reset, ow_reset_search, ow_skip, ow_depower = + ow.setup, ow.search, ow.select, ow.read, ow.read_bytes, ow.write, ow.crc8, + ow.reset, ow.reset_search, ow.skip, ow.depower + +local node_task_post, node_task_LOW_PRIORITY = node.task.post, node.task.LOW_PRIORITY +local string_char, string_dump = string.char, string.dump +local now, tmr_create, tmr_ALARM_SINGLE = tmr.now, tmr.create, tmr.ALARM_SINGLE +local table_sort, table_concat = table.sort, table.concat +local file_open = file.open +local conversion + +local DS18B20FAMILY = 0x28 +local DS1920FAMILY = 0x10 -- and DS18S20 series +local CONVERT_T = 0x44 +local READ_SCRATCHPAD = 0xBE +local READ_POWERSUPPLY= 0xB4 +local MODE = 1 + +local pin, cb, unit = 3 +local status = {} + +local debugPrint = function() return end + +-------------------------------------------------------------------------------- +-- Implementation +-------------------------------------------------------------------------------- +local function enable_debug() + debugPrint = function (...) print(now(),' ', ...) end +end + +local function to_string(addr, esc) + if type(addr) == 'string' and #addr == 8 then + return ( esc == true and + '"\\%u\\%u\\%u\\%u\\%u\\%u\\%u\\%u"' or + '%02X:%02X:%02X:%02X:%02X:%02X:%02X:%02X '):format(addr:byte(1,8)) + else + return tostring(addr) + end +end + +local function readout(self) + local next = false + local sens = self.sens + local temp = self.temp + for i, s in ipairs(sens) do + if status[i] == 1 then + ow_reset(pin) + local addr = s:sub(1,8) + ow_select(pin, addr) -- select the sensor + ow_write(pin, READ_SCRATCHPAD, MODE) + local data = ow_read_bytes(pin, 9) + + local t=(data:byte(1)+data:byte(2)*256) + -- t is actually signed so process the sign bit and adjust for fractional bits + -- the DS18B20 family has 4 fractional bits and the DS18S20s, 1 fractional bit + t = ((t <= 32767) and t or t - 65536) * + ((addr:byte(1) == DS18B20FAMILY) and 625 or 5000) + local crc, b9 = ow_crc8(string.sub(data,1,8)), data:byte(9) + + if unit == 'F' then + t = (t * 18)/10 + 320000 + elseif unit == 'K' then + t = t + 2731500 + end + local sgn = t<0 and -1 or 1 + local tA = sgn*t + local tH=tA/10000 + local tL=(tA%10000)/1000 + ((tA%1000)/100 >= 5 and 1 or 0) + + if tH and (t~=850000) then + debugPrint(to_string(addr),(sgn<0 and "-" or "")..tH.."."..tL, crc, b9) + if crc==b9 then temp[addr]=t end + status[i] = 2 + end + end + next = next or status[i] == 0 + end + if next then + node_task_post(node_task_LOW_PRIORITY, function() return conversion(self) end) + else + --sens = {} + if cb then + node_task_post(node_task_LOW_PRIORITY, function() return cb(temp) end) + end + end +end + +conversion = (function (self) + local sens = self.sens + local powered_only = true + for _, s in ipairs(sens) do powered_only = powered_only and s:byte(9) ~= 1 end + if powered_only then + debugPrint("starting conversion: all sensors") + ow_reset(pin) + ow_skip(pin) -- skip ROM selection, talk to all sensors + ow_write(pin, CONVERT_T, MODE) -- and start conversion + for i, _ in ipairs(sens) do status[i] = 1 end + else + local started = false + for i, s in ipairs(sens) do + if status[i] == 0 then + local addr, parasite = s:sub(1,8), s:byte(9) == 1 + if parasite and started then break end -- do not start concurrent conversion of powered and parasite + debugPrint("starting conversion:", to_string(addr), parasite and "parasite" or "") + ow_reset(pin) + ow_select(pin, addr) -- select the sensor + ow_write(pin, CONVERT_T, MODE) -- and start conversion + status[i] = 1 + if parasite then break end -- parasite sensor blocks bus during conversion + started = true + end + end + end + tmr_create():alarm(750, tmr_ALARM_SINGLE, function() return readout(self) end) +end) + +local function _search(self, lcb, lpin, search, save) + self.temp = {} + if search then self.sens = {}; status = {} end + local sens = self.sens + pin = lpin or pin + + local addr + if not search and #sens == 0 then + -- load addreses if available + debugPrint ("geting addreses from flash") + local s,check,a = pcall(dofile, "ds18b20_save.lc") + if s and check == "ds18b20" then + for i = 1, #a do sens[i] = a[i] end + end + debugPrint (#sens, "addreses found") + end + + ow_setup(pin) + if search or #sens == 0 then + ow_reset_search(pin) + -- ow_target_search(pin,0x28) + -- search the first device + addr = ow_search(pin) + else + for i, _ in ipairs(sens) do status[i] = 0 end + end + local function cycle() + if addr then + local crc=ow_crc8(addr:sub(1,7)) + if (crc==addr:byte(8)) and ((addr:byte(1)==DS1920FAMILY) or (addr:byte(1)==DS18B20FAMILY)) then + ow_reset(pin) + ow_select(pin, addr) + ow_write(pin, READ_POWERSUPPLY, MODE) + local parasite = (ow_read(pin)==0 and 1 or 0) + sens[#sens+1]= addr..string_char(parasite) + status[#sens] = 0 + debugPrint("contact: ", to_string(addr), parasite == 1 and "parasite" or "") + end + addr = ow_search(pin) + node_task_post(node_task_LOW_PRIORITY, cycle) + else + ow_depower(pin) + -- place powered sensors first + table_sort(sens, function(a, b) return a:byte(9)= 5 and 1 or 0) - - if tH and (t~=850000) then - debugPrint(to_string(addr),(sgn<0 and "-" or "")..tH.."."..tL, crc, b9) - if crc==b9 then temp[addr]=(sgn<0 and "-" or "")..tH.."."..tL end - status[i] = 2 - end - -- end integer version - else - -- float version - t = t / 10000 - if math_floor(t)~=85 then - if unit == 'F' then - t = t * 18/10 + 32 - elseif unit == 'K' then - t = t + 27315/100 - end - debugPrint(to_string(addr), t, crc, b9) - if crc==b9 then temp[addr]=t end - status[i] = 2 - end - -- end float version + debugPrint(to_string(addr), t, crc, b9) + if crc==b9 then temp[addr]=t end + status[i] = 2 end end next = next or status[i] == 0