Remember to clear browser cache to get new interface!
Note: New log format after V1.2.7&v2.0!
Note: default username/password/hostname changes to brewpiless after v1.2.7
Note: The code is now built in PlatformIO.
- I2C LCD support
- Rotary Encoder support (* not supported by default)
- Remote LCD display on browser
- Remote Temperature control
- Temperature schedule
- Device(temperature sensor and actuator) setup
- Temperature logging to specified remote destination.
- Web-based OTA firmware update.
- Web-based network setting
- SoftAP mode
- Local Temperature log and temperature chart
- Gravity logging. The gravity data can be manually input or from iSpindel.
- iSpindel support.
- Gravity-based temperature schedule.
- Save and resuse of beer profiles.
- Static IP setting.
- Export saved datat to csv format by offline log viewer.(new!)
This project uses a single ESP8266 to replace RPI and Arduino.
BrewPi is the greatest, if not the ultimate, fermentation temperature controller. The original design uses a RPI to log temperatures and maintain a temperature schedule. The RPI also hosts a web server as the front-end of internet web access.
Using a RPI or a PC allows the maximum power of BrewPi to be used but with the additional of a RPI or PC.
ESP8266 is cheap and powerful WiFi-enabling IOT solution. Although it can't be as powerful as a RPI, it's a good solution to maximize the functionality and minimize the cost. Using a single ESP8266 as the temperature controller(replacing Arduino), web server and schedule maintainer(replacing RPI) also reduces the work in building a brewpi system.
Uploading files to ESP8266 is no longer needed because the "files" are now embedded in the code. However, you can still upload files to the File System by using the Data Upload tool or web based file manager. The file in File System takes higher priority. That is, if you have an "index.htm" in the file system, you will get this file instead of the server page embedded within the code when you visit "http://brewpiless.local". If you have ever uploaded the data folder using the upload tool, please delete this when you update to new version, or you will not get updated files. Please also note that you might need to hit "refresh" button on your browser to force it to get new files.
The difference bewteen v1.2.7 and v.20 is
- v2.0 uses gravity-based beer profile while v1.2.7 uses BrewPi style beer profile.
- v2.0 supports profile re-use.
To build v1.2.7 from source. Open espconfig.h, and change line 29
#define EnableGravitySchedule false
- ESP8266 won't restart after saving system configuratoin. Sometimes ESP8266 can't restart by Software watchdog timer reset, which is the only way to reset the system by software. It did happened on my NodeMcu and D1 mini boards that didn't connect to anything but USB. I have no solution for it.
- ESP8266 won't start after selecting WiFi network. The web server used is ESPAsyncWebServer which uses ESPAsyncTCP. I found that if ESP8266 ever enters SoftAP mode before connecting to the network, the Web server will fail on tcp_bind() and the web service will be unavailable. Not tracing the source code of the LWIP, I just worked around by reseting the system. However, ESP8266 sometimes doesn't reset.
- The page can't be loaded correctly. It rarely happens after HTTP caching is used, but it does happen especially when Javascript Console is opened. During developing and testing, I found corrupted html/javascript pages. Without the abliity and time to debug or develop the web server and or TCP/IP stack, I decide to live with it.
- Incorrect tempeerature chart. The log format before v2.0 is vulnerable. There seems to be some unconsidered conditions that break the log.
-
v2.3.3
- All HTML files can be replaced by files on SPIFFS. Gzip support.
- updated HTML/JS
- Add "Title" to be displayed at banner in config page.
- Workaround for accepting HTTP Post body length not equal to Content-Length.( for iSpindel v5.2+)
-
v2.3.2
- Beer Profile scheculde bug fix
- Show hostname at banner
-
v2.3.1
- WiFi signal
- /getstatus web service
-
v2.3
- Fix error in time of reset. (New log format! Use new log viewer)
- State coloring in chart
- Remove "view" action in log list.
-
v2.2
- 4 decimals of gravity
- Switch to PlatformIO instead of Arduino IDE.
-
v2.1
- more gravity-based condition
-
v2.0
- gravity-based beer profil schedule
-
v1.2.7
- iSpindel support
BrewPi related configuration is defined in config.h while networking related configuration is defined in espconfig.h. They are both self-explanatory and commented. Please check the files directly.
You will need the ESP8266/Arduino environment, as well as the following libraries.
- ArduinoJson https://github.com/bblanchon/ArduinoJson
- WiFiManager (my branch) https://github.com/vitotai/WiFiManager
- ESPAsyncTCP https://github.com/me-no-dev/ESPAsyncTCP
- ESPAsyncWebServer https://github.com/me-no-dev/ESPAsyncWebServer
- ESP8266HTTPUpdateServer (newer version is needed. you might need to manually download the files.) https://github.com/esp8266/Arduino/tree/master/libraries/ESP8266HTTPUpdateServer
- OneWire https://github.com/PaulStoffregen/OneWire
Some of the libraries are modified and provided. Please use the libraries provided to ensure compatiblity.
WiFi Manager is used to setup the the network. On first use or if the connected network changes or disappears, WiFi Manager will
setup a AP named brewpiless. The network setting can be done through the web page after connecting the ESP8266 as AP.
Please check URL for more detail.
https://github.com/tzapu/WiFiManager
After three minutes, ESP8266 will proceed to enter soft AP mode. That means you only have three minutes to setup the network.
BrewPiLess now can run in AP mode, which enables it to run as stand alone device. The newly modified WiFiManager has a new option, "Soft AP Mode". Soft AP mode will also be entered if the network setting is not configured in three minutes (and previous connected network doesn't exist, or there is no previously connected network.) This design is to enable recovery from a power shortage or system reset. Without this feature, BrewPiLess will hang at the network setting state and won't perform temperature management funcitons.
For scheduled temperature management, aka Beer Profile mode, the "time" information is needed to manage the temperature, but an NTP server will not be accessible without an internet connection. Therefore, manual setup of "time" is necessary in this mode. In page of "Temperature Management", aka /control.htm, a SET TIME button will be shown when the time of ESP8266 is far away from the computer/phone. Pressing that button will set the time of ESP8266 to the time of the computer/phone, or the browser to be exact.
To enable automatic recovery from power shortage or system reset, the time informatoin is saved periodically and restored at boot-up if NTP is not accessible, which means the duration of power shortage is assumed to be zero. If the power shortage lasts too long, the shedule will not be on track. For example, if the power shortage lasts 8 hours, the schedule will be off for 8 hours since that 8 hours is missing for ESP8266. Without a RTC, this might be the best I can do.
mDNS doesn't work under AP mode. Therefore, "brewpiless.local" can not be used under AP mode, but "brewpiless.org" will do the job. In fact, all domain names except those in Apple's Captive Portal checklists will do.
After v2.0, static IP is supported at the page of network selection. To use DHCP, leave the IP blank.
BrewPiLess implements mDNS, so you can use "brewpiless.local" instead of the IP address if you are using platforms from Apple. You can change the name in system configuration page.
Default username and password are both brewpiless. (It was brewpi before 1.2.6.)
-
Main page -
http://brewpiless.local/The main page. The menu includes:- Device setup -
http://brewpiless.local/setup.htmThe device setup procedure as original BrewPi is necessary. - Logging setting -
http://brewpiless.local/log - System configuration -
http://brewpiless.local/configUpdating the settings will result in restart of the system. - Gravity Sensor Gravity sensor(iSpindel) settting.
- Device setup -
-
LCD page -
http://brewpiless.local/lcdThe LCD display of BrewPi. Clicking the LCD brings out the pop menu to other functions. This page is good for mobile device or when temperature chart is not necessary. -
OTA update -
http://brewpiless.local:8008/systemupdateThe menu from the main page doesn't include this page.
To add gravity reading record, click the SG reading. The number entered with the time when it is entered will be saved as a SG reading record. To enter OG, click the OG value. Once OG is availble, the Attenuation and ABV will be calcuated when SG reading is updated. The OG is for calculation of attenuation and ABV only.
This workaround is in iSpindel 5.2.1.
For 5.2.0, without this modification, BrewPiLess will crash after 5 times of report.
There is an issue of ESP8266. (To be more specific, it is an issue of LWIP or TCP/IP.) The issue is described here: esp8266/Arduino#2750
The work-around for it is add a delay(50); aftet finishing data report and before ESP8266 goes into deep sleep, so that ESP8266 has a chance to close the connection.
BrewPiLess supports iSpindel by accepting data from iSpindel and acting an AP for iSpindel to connect to, BrewPiLess and iSpindel can connect to the same router.
To support softAP, set the correct settings in System configuration. Please note that the password(passphrase) should be at least 8 characters. The same password(pass phrase) is used for setting and for connection certification. Default value is brewpiless.
| Setting | Description |
|---|---|
| iSpindel | To enable iSpindel support. |
| Calculated by BPL | Do the conversion from tilt angle to gravity by BrewPiLess. If this option is OFF, all the following options are not used. |
| SG Calibration | Offset of gravity reading. This value will be applied(add) to the calcuated SG if SG is calculated by BrewPiLess. |
| Temp. Correction | Apply temperature correction to the calculated gravity reading. Celsius only. Usually it is 20°C(68°F) or 15°C(59°F). |
| Coefficients | The coefficients of the formula to calculate gravity. Note: this set of coefficients is for calcuation of specific gravity, not plato. Use 0 for x^3 term if quadratic polynomial is used. |
| LowPass Filter Coefficient | 0~1. See following description |
| Gravity Stability Threshold | Integer value. 1 point = 0.001. |
About low Pass Filter:
The coefficient defines the 'a' in this LPF:
y = y[i-1] + a ( x - y[i-1] )
It is usually set to 1/f. So, 1/60 for one minute reporting period, and 1/6 for 10 minute reporteing period.
Note: enabling iSpindel setting only enables the initial display of iSpindel status. The gravity report will be processed even when the option is OFF.
calibrationSG.htm in /extra folder is an utility HTML file which can be used to derive the coefficients instead of using the excel from iSpindel.
- the iSpindel Name must start with
iSpindel, likeiSpindel000 - Select
Generic HTTP - Server address set to
192.168.4.1if iSpindel connect to the AP created by BrewPiless. or use the ip of BrewPiless if iSpindel connects the AP that BrewPiLess connects to. - set url to
/gravity
For other iSpindel setting, like network settting, please refer to iSpindel project.
- The log won’t start automatically, you have to start it at log setting page.
- (new in v1.2.5) When logging is not started, BrewPiLess still logs the data and keep that latest 2 to 3 hours of data. The data will not be saved to file system, though.
- The temperatures are logged every minute.
- A 30 day log will take around 350k bytes. That might imply that 3M space can record around 6 month data. However, there is no guarantee of the robustness of SPIFFS.
- Changing temperature when logging will result in wrong data interpretation.
- A maximum of 10 logs is allowed. The logs will not be deleted automatically. Manual deleting is necessary.
- Off-line viewer is available. You can download the log and view it from your computer. Download the file "BPLLogViewer.htm" in the "extra" subfolder. Save it anywhere in your computer. Open it using a web browser.
- Internet access is required to view the chart. To save some more space and to alleviate the loading of ESP8266, the library is not put in the ESP8266. (It is possible after v1.2.5.)
- The loggging format changed after v1.2.7/v2.0. Use BPLLogViewerV2.htm to view the new logs and BPLLogViewer.htm for old logs. The old logs cannot be viewed 'on-line' by the "view" button. Please download them and view by the off line viewer.
There are two wasy that make it possible to have the temperature chart under AP mode.
- Let the browser cache the file. The simple way is having BrewPiLess connect to a router that has internet access, then connnection to BrewPiLess. Usually, the browser will cache the library laod from disk after that. However, the browser might clear the cache for some reasons, so this might not always work.
- Put the library in ESP8266.
Go to http://dygraphs.com/download.html and download the v1.1.1
dygraph-combined.js. open http://brewpiless.local:8008/filemanager, and upload the downlowed libarry to ESP8266. The file shoule be named exactdygraph-combined.js.
Remote logging can be used to post data to a HTTP server that BrewPiLess can connect to.The format field in log setup page is like the format in printf but uses the following specifiers:
| Specifier | output |
|---|---|
| %b | Beer temperature |
| %B | Beer setting |
| %f | fridge temperature |
| %F | fridge setting |
| %r | room temperature |
| %g | gravity |
| %a | auxiliary temperature |
| %v | external device voltage |
| %u | UNIX timestamp of last gravity update |
For example, let beer setting be 20.0 and beer temperature be 18.3, if the format is api_key=TheRealApiKeyHere&field1=%B&field2=%b,
the data will be api_key=TheRealApiKeyHere&field1=20.0&field2=18.3.
If the method is GET, the data will append to the url with additional ?, so the result will be
http://api.thingspeak.com/update?api_key=TheRealApiKeyHere&field1=20.0&field2=18.3.
(GET is usually not recommended.)
The Data Type field is used as "Content-Type" in HTTP protocol. When it is left blank, the default value of application/x-www-form-urlencoded will be used. The default type is good for content like A=V1&B=V2.
Example setting for Thingspeak.com
Example setting for ubidots.com
Use Save As button to save the edited profile. The saved name should not contain special characters.
Use ... button next to Save As button to open and close the profile list. After loading the profile by clicking it on the list, you have to Save it before Applying it.
A beer profile is specified by a series of temperature stages. There are two types of temperature stages, hold and ramp. In hold stage, the temperature is controlled at the specified temperature until the specified condition meets.
In ramp stage, the temperature changes gradually toward the next stage. A ramp stage will be automatically inserted between two hold stages. Only the time, in unit of day, can be specified for a ramp stage.
Three conditons and their combinations can be used to specify the condition for a hold stage to finish.
-
Time(Days)
Time is specified in unit of day. Time must be specified no mater what kind of condition is specified. It servers two purposes: for drawing the temperature chart and guestimate of current stage under certain conditions.
-
Gravity(SG)
The condition meets when the gravity reading is less than or equal to the specified value. The value can be specified as absolute values like 1.012 or percentage of attenuation like 70%. If percentage of attenuation is used, the original gravity must be specified before applying the beer profile.
-
Stable reading of gravity(Stable)
It is specified in unit of hour. Maximum value is 72. The definition of "stability" is when the difference between the lastest gravity reading and previous gravity reading is less to or equal to a threshold, default to 1. Set this threshold value in the
Gravity Sensorsetting page. To specify a specific value of ponts, use the notation:Gravity@Hours. For example, the condition of4@48will meet when the gravity change is less than or equal to (<=) 4 in 48 hours.
It is recommended to use other condition with stable reading. The fermentaton usually kicks off after a period of lag. The lag usually takes from 10 hours to 24 hours. During lag time, the reading is stable.
Note:
- The values used by beer profile are filtered values. Checked iSpindel Support for detail information.
- Attunation percentage is supported for convenience of profile reuse. The real condition is based on gravity reading by simply multiplying the percentage to the original gravity. The computation is done when the profile is "loaded". Changing the OG after "applying or saving" beer profile has no effect on beer profile.
BrewPi(Less) is designed to control fermenting temperature in a fridge or freezer. To control glycol cooling, some hacks are necessary:
-
build with GlycolSupport option enabled It's simple by adding
-DGlycolSupport=trueto build flag in platformio.inibuild_flags = -Wl,-Tesp8266.flash.4m.ld -DGlycolSupport=true -
Set minimum cooling/heating on/off time open the page
http://brewpiless.local/testcmd.htmSet the following options:minCoolTime,minCoolIdleTime,minHeatTime,minHeatIdleTIme,deadTime. ThedeadTimeis the minimum time between cooling and heating. It also defines the minimum waiting time after booting up. Issue a command like this to set minimum cooling on and off to 10 seconds:j{"minCoolTime":10,"minCoolIdleTime":10} -
Set P.I.D. parameter Setting all P.I.D. to zero will result in the "fridge set" equal to "beer set".
j{"Kp":0,"Ki":0,"Kd":0}You can use
c(yes, only one single lower case "c" character.) to read back the setting value. If the values don't change, you might need to erase the flash. -
Use only beer sensor and control the pump. The fridge temperature will read from beer sensor.
Special Note:
You might notice that temperatures of beer and fridge from the same sensor are different. The reason is the values are filtered and and they have different filtering parameters. Those parameters also can be changed by the JSON commands. fridgeFastFilt, fridgeSlowFilt, firdgeSlopeFilt, beerFastFilt, beerSlowFilt, and beerSlopeFilt.
Fortunately, 3.3V is regarded as HIGH in 5V logic, so the output of ESP8266 can be connected directly to the devices. Luckily, DS18B20 works under 3.3V. I just replace the Arduino Nano with the ESP8266, and it works. You should still be careful not to burn the ESP8266.
A lot of PINs are required, so ESP-12 or ESP-07 should be a better choice. NodeMcu development board is a simple solution for those who arn't good at soldering.
Search the BrewPi DIY on homebrewtalk.com forum to find out the hardware setup, but use these ESP8266 pins in place of Arduino pins.
This is default configuration, you can change it in config.h.
| ESP8266 GPIO | NodeMcu Label | Connect to |
|---|---|---|
| GPIO16 | D0 | Buzzer |
| GPIO5 | D1 | I2C SCL |
| GPIO4 | D2 | I2C SDA |
| GPIO0 | D3 | INT from PCF8574 * Or Wakeup Button |
| GPIO2 | D4 | Door (not used) |
| GPIO14 | D5 | Cooling Actuator* |
| GPIO12 | D6 | Temperature Sensors |
| GPIO13 | D7 | Heating Actuator* |
| GPIO15 | D8 |
*cooling/heating actuator PINs are configurable.
Note: The GPIOs of ESP8266 are not all General Purpose. Some of them has special functions, and might not be usable. For example, some PINs on my NodeMcu board don't work normally. !!Important !! It is hightly recommended to pull up GPIO0 and GPIO2 while pull down GPIO15 so that the system will start up normally instead of staying in bootrom mode in case the system crashes. Updating the system configuration and firmware also results in restart of system, and sometimes this issue happens if the circuit isn't implementated. Check this url for detail information: https://github.com/esp8266/Arduino/blob/master/doc/boards.md#minimal-hardware-setup-for-bootloading-and-usage
!! The rotary encoder is not supported by directly connecting it to ESP8266. That will prevents ESP8266 to boot up when the rotary encoder is at certain positions.!!
Due to the special usage at bootup of GPIO0,2,15(D3,D4,D8), they can't be used as inputs for rotary encoder. One of the solution is buy an IO Expander. Currently, PCF8574 is supported if you really need the rotary encoder. You will have to change the compile options in Config.h to enable this feature.
Without a rotary encoder input, the backlight of the LCD will never be turned-off because there is no way to "wake" it up. Since BrewPiLess can be controlled by network easily, the rotary encoder seems unnecessary. A wake-up button is a solution for this. The button connects to D3 by default and grounds D3 when pushed.
Although the flash size of ESP8266 module might be as big as 16 Mega bytes, it is still limited. The logs can be downloaed and viewed offline. Goto Extra folder and download the BPLLogVewer.htm/BPLLogVewerV2.htm. Place them anywhere on your computer, and open it by your browser.
BPLLogVewerV2.htm is for logs created by v2.0/v1.2.7 or after, while BPLLogVewer.htm is for logs created by older version.
The data can be exported as CSV(comma seperated value) file by offlie log viewer. The time exported is Unix time(EPOC time).
Due to the resource limit of ESP8266, establishment of HTTPS connection while serving other functions will crash the system.
Therefore, a generic interface is provided to enable pushing/sending data to a specified URL(HTTP, NO HTTPs). The file to support Google Sheet logging is in extra folder.
A simple script as the proxy to push data to Google Sheet is needed. Here is how to do it.
- Create a script to access Google Sheet.
a. you must have a google account. obviously.
b. got to “script.google.com”, create a new project, and copy the content of code.gs in extra folder.
c. release it as a Web Application, and set it to “Run as ME” and "anyone can access.” Note the script ID in the URL
- Create a Spread Sheet for logging.
a. Create a google spreadsheet in any name you like, but note the spreadsheet ID. input the lables at cell 'A1', and 3rd rows. leave 2nd row empty. like this. You might need to manually change the format of Time column to display Date & Time. The default format seems to show Date only.
| A | B | C | D | E | |
|---|---|---|---|---|---|
| 1 | Last Update: | ||||
| 2 | |||||
| 3 | Time | BeerTemp | BeerSet | FridgeTemp | FridgeSet |
| 4 |
b. rename or keep the sheet label. note it
- Setup proxy script. you must have access to a server that you can run your CGI script and the CGI script can connect to other hosts.
Do it yourself or ask someone for help. The URL that we will use is this script.
- Settings
In the log setting pages, default to
http://brewpiless.local/log
-
URL: http://
{your server}/{your path}/logdata.php <= your script in step 3 -
Method: POST
-
format:
script=[script_ID]&ss=[spreadsheet_ID]&st=[sheet_label]&pc=thisistest&bt=%b&bs=%B&ft=%f&fs=%F- [script_ID] is the id from step 1c
- [spreadsheet_ID] is from step 2a
- [sheet_label] is the value in step 2b
thisistestis the passcode for google script app.
-
Log time period. <= set the value you like, in seconds.
Then, BrewPiLess will post temperature data to the URL, and the script(logdata.php) at that URL will get the data and do HTTPS request to google script which write the data to the specified spreadsheet.
If you write your own proxy script or push data to other IOT website. you can change the settings to your needs.
The periodical request can be also used as an I-AM-ALIVE message. For example, if the period is set to 10 minutes, and the temperature hasn't been updated for 11 minutes,
there must be something wrong. /extra/brewpimon.php is an example which is executed by cronjob every few minutes to check the updating of temperature data. The PHP will notice by email if the temperature data isn't updated in specified time.
** In newer version, those files are embedded in the code, and it is not necessary to upload them. ** To upload files onto ESP8266, check the following link: https://github.com/esp8266/Arduino/blob/master/doc/filesystem.md
In newer version, the basic files are embedded. However, the file in SPIFFS takes higher prioity. That will be useful if you want to change them.
Two additional tools are available. One is web-based file manager to manipulate the files directly from the web. You can download and upload files the the web.
To enable this feature, set DEVELOPMENT_FILEMANAGER to true in espconfig.h.
You can access the files by the url (you should know you can change it):
http://brewpiless.local:8008/filemanager
The second tool is used to access the BrewPi directly. The original BrewPi on Arduino uses serial to communicate with RPI in the JSON-like format.
By using the JSON-like commands, you have full access to BrewPi.
For example, you can erase the EEPROM by sending E letter, get the LCD display by issuing l command, and get device list by h command.
The page is at
http://brewpiless.local/testcmd.htm
By using http://brewpiless.local/testcmd.htm, you can control BrewPi core directly. For example, to set temperature to Fahrenheit. Open the testcm.htm page, and enter the following string, and send.
j{"tempFormat":"F"}
You can set multiple parameters in one command. The command after j is in formal JSON format. Please include the double quote(") for key and string value.
| Key | Meaning | Note |
|---|---|---|
| tempFormat | Temperature format | F for Fahrenheit, C for Celius |
| tempSetMin | Minimum setting temperature | |
| tempSetMax | Maximum setting Temperature | |
| pidMax | PID Max | |
| Kp | Kp parameters of PID | |
| Ki | Ki parameters of PID | |
| Kd | Kd parameters of PID | |
| iMaxErr | iMaxError | |
| idleRangeH | idleRangeHigh | |
| idleRangeL | idleRangeLow | |
| heatTargetH | heatingTargetUpper | |
| heatTargetL | heatingTargetLower | |
| coolTargetH | coolingTargetUpper | |
| coolTargetL | coolingTargetLower | |
| maxHeatTimeForEst | maxHeatTimeForEstimate | |
| maxCoolTimeForEst | maxCoolTimeForEstimate | |
| fridgeFastFilt | fridgeFastFilter | |
| fridgeSlowFilt | fridgeSlowFilter | |
| fridgeSlopeFilt | fridgeSlopeFilter | |
| beerFastFilt | beerFastFilter | |
| beerSlowFilt | beerSlowFilter | |
| beerSlopeFilt | beerSlopeFilter | |
| lah | lightAsHeater | |
| hs | rotaryHalfSteps | |
| heatEst | heatEstimator | |
| coolEst | coolEstimator |
The command to set sensor calibration is
U{i:0,j:0.36}
where 0 is the device ID that is assigned to the sensor during device setup, and 0.36 is the adjustment to the sensor.
To reset WiFi setting, use the following URL (assuming you can access it by brewpiless.local.)
http://brewpiless.local/erasewifisetting
BrewPiLess will erase the wifi setting and then reset.
For those who don't have access to Microsoft Excel like me, the calibrationSG.htm in /extra folder can be used to get the formula. The generated formula calculates specific gravity like 1.012 instead of plato.
Note: I don't have access to MS Excel, so I am not sure if it is exactly the same as the way iSpindel does it. It works pretty good for me, though.
-
Q: I can't save the device setting.
A: Click the "Erase Setting" and try again.
-
Q: The meaing of WiFi signal.
A:
| bars | Signal Strength | Note |
|---|---|---|
| 4 | > -67 dBm | Very good. |
| 3 | -67 ~ -70 dBm | good. |
| 2 | -70 ~ -80 dBm | minimum for reliable connectivity. |
| 1 | -80 ~ -90 dBm | minimum for basic connectivity. unreliable. |
| 0 | < -90 dBm | Unstable signal |
-
Q: The mode(beer constant or fridge constant) is not kept after reset.
A: Please make sure the EEPROM is "formated", which is done by "Erase Setting".
-
Q: How to recover default settings.
A: "Erase Setting". The hardware configuration will be gone after erasing. You might need to save the hardware configuration and restore after erashing.