System Functions

The functions listed here can be used in expressions in Comfile Studio.

• asin(value) : Arc-Sine
• acos(value) : Arc-Cosine
• atan(value) : Arc-Tangent
• avg(x,y,z,…) : Returns the average of all values in the argument list
• ceil(value) : Rounds number up to the nearest integer value.
• cos(value) : Cosine
• cosh(value) : Hyperbolic Cosine
• exp(value) : e raised to a given exponent
• fabs(value) : absolute value
• fmod(x,y) : the remainder of x divided by y.
• floor(value) : Rounds number down to the nearest integer value.
• log(value) : Natural Logarithm
• log10(value) : Log base 10
• max(x,y,z,…) : Returns the largest value from the argument list
• min(x,y,z,…) : Returns the smallest value from the argument list
• max_index(x,y,z,…) : Returns the index of the largest value in the argument list
• min_index(x,y,z,…) : Returns the index of the smallest value in the argument list
• pow(x,y) : x raised to the power y
• sin(value) : Sine
• sinh(value) : Hyperbolic Sine
• sqrt(value) : square root
• stdev(x,y,z,…) : Returns the standard deviation of all values in the argument list
• tan(value) : Tangent
• tanh(value) : Hyperbolic Tangent

• bit(subject, bitIndex) : Returns the value of the bit at bitIndex in subject. subject can be an expression or a variable name, but if it is a variable name, it must must be enclosed in double quotes. bitIndex can be an integer from 0 through 31.

  bitValue = bit("a", 3)
  bitValue = bit(a + 3, 1)

• set_bit("variable_name", bitIndex, value = 1) : Sets the value of the bit at bitIndex in variable_name to value. variable_name is a variable name that must be enclosed in double quotes. bitIndex can be an integer from 0 through 31. value is optional and defaults to 1.

  set_bit("a", 3, 1)

• toggle_bit("variable_name", bitIndex, value) : Toggles the value of the bit at bitIndex in variable_name. variable_name is a variable name that must be enclosed in double quotes. bitIndex can be an integer from 0 through 31.

  toggle_bit("a", 3)

• find_text(string_to_search, string_to_find) : Returns the character index of string_to_find in string_to_search. Returns -1 if not found.
• num_to_text_int(number) : Prints a number as a base 10 integer character string.
• num_to_text_int(number, digits) : Prints a number as a base 10 integer character string with leading 0's. Ex: num_to_text_int(3.14, 4) prints “0003”.
• num_to_text_hex(number) : Prints a number as a base 16 integer character string.
• num_to_text_hex(number, digits) : Prints a number as a base 16 integer character string with leading 0's
• text_hex_to_num(hexadecimal_string) : Returns the binary number corresponding to hexadecimal_string. For example, if hexadecimal_string is “FF”, 255 will be returned.
• num_to_text_dec(number, fractional digits) : Prints a number as a base 10 character string with a given number of fractional digits. Ex: num_to_text_dec(3.14159, 4) = “3.1416”
• text_starts_with(target_string, prefix, ignore_case): Returns 1 if target_string begins with prefix. Returns 0 otherwise. If ignore_case is non-zero it will do a case-insensitive search. ignore_case defaults to 0.

  text_starts_with("BREAKFAST", "break")    // Returns 0
  text_starts_with("BREAKFAST", "BREAK")    // Returns 1
  text_starts_with("BREAKFAST", "break", 1) // Returns 1
  text_starts_with("BREAKFAST", "break", 0) // Returns 0

• text_ends_with(target_string, suffice, ignore_case): Returns 1 if target_string ends with suffix. Returns 0 otherwise. If ignore_case is non-zero it will do a case-insensitive search. ignore_case defaults to 0.

  text_ends_with("BREAKFAST", "fast")    // Returns 0
  text_ends_with("BREAKFAST", "FAST")    // Returns 1
  text_ends_with("BREAKFAST", "fast", 1) // Returns 1
  text_ends_with("BREAKFAST", "fast", 0) // Returns 0

• text_to_num(string) : Parses a character string in base 10.
• replace_text(string_to_search, string_to_find, replacement) : Replaces any occurrence of string_to_find in string_to_search with replacement. String variable names must be enclosed in double quotes with the $ prefix omitted.

  $var = "I ate lunch."; Replace_text("var", "lunch", "dinner")

Text memory is a specific string memory area in the HMI runtime. The contents are lost when the panel PC is powered off. It is similar to internal memory except it stores strings. The default capacity of the text memory is 1024 strings (0 ~ 1023) and each string is default initialized to an empty string. The capacity can be expanded with the set_tmem_size function.

• set_tmem_size(maximum possible number of strings): Sets the maximum capacity of text memory up to 100,000 strings.
• tmem(address): Reads a value from a specific address (i.e. index) in text memory.
• set_tmem(address, "string value"): Writes a string at a specific address (i.e. index) in text memory. You can increase the parameters by concatenating them with commas to record the string consecutively. Example: set_tmem(10,"one","two","three") will set strings at address 10, 11, and 12 respectively.
• text_split("string","separator", start address to contain the result, maximum number of results): Divides the string with a specific separator and writes the result to text memory. The maximum number of outputs is optional. Example: If text_split("a#b#c#d"),"#",10,3) is executed, “a” will be written to address 10, “b” will be written to address 11, and “c” will be written tot address 12.
• text_merge(start address, number, "separator"): Concatenates strings in text memory joined by a separator and returns the result as a single string. Example: If text_merge(10,3,"-") is executed when “aa” is at address 10, “b” is at address 11, and 'c' is at address 12, the string “aa-bc” is returned.

The following functions can be used to detect communication problems between the ComfileHMI and the PLC.

• timeout_result() : Returns 1 if the last communication resulted in a timeout waiting for a response. Return 0 if no timeout occurred.
• timeout_count() : Returns the total number of times a communication timeout occurred since the project was executed.
• reset_timeout_count() : Resets the timeout count returned from timeout_count() to 0.

The following functions are used to read from and write to internal memory.

• set_mem(index, value) : Writes value to internal memory at index.
• mem(index) : Reads the value current stored in internal memory at index.
• set_mem(index, value1, value2, …, valueN)

• base64_to_file(base64_string, file_path, append) : Decodes base64_string and saves it to the the file specified by file_path. If append is 1 the data is appended to the end of the file. If append is 0, the file is overwritten.

  base64_to_file($base64_data, "storage card\myfile.bin", 1)

• delete_file(file_path): Deletes the file from the file system.
• delete_folder(folder_path) : Deletes the folder and all containing subfolders from the file system.

  delete_folder("storage card\folder1")

• ensure_folder_exist(folder_path) : Ensures a folder exists. The folder, and any required parent folders, are created if it does not exist.

  ensure_folder_exist("storage card\folder1\folder2")

• file_exists(file_path): Returns 1 if file_path exists, 0 if not.

  file_exists("storage card\myfile.txt") == 1

• file_to_base64(file_path): Returns the contents of the file specified by file_path as a base 64 string.

  $base64_data=file_to_base64(“storage card\data.bin")

• file_to_text(file_path): Returns the contents of file_path as a string. If the file's contents have the byte-order mark FF FE, the contents of the file will be Unicode encoded.

  $content = file_to_text("storage card\myfile.txt")

• text_to_file(string, file_path): Stores string variable string to the file file_path.

  text_to_file($content, "storage card\myfile.txt")

• file_size(file_path): Returns the size of the given file in bytes.
• rename_file(existing_file_path, new_file_path): Renames existing_file_path to new_file_path.

• write_byte(value): Writes a single byte of binary data to the response of a remote script. Returns 1 on success and 0 on failure.
• write_word(value): Writes 2 bytes of binary data in little endian to the response of a remote script. Returns 1 on success and 0 on failure.
• write_dword(value): Writes 4 bytes of binary data in little endian to the response of a remote script. Returns 1 on success and 0 on failure.
• write_text(string): Writes a UTF-8 string to the response of a remote script. Returns 1 on success and 0 on failure.
• write_file_contents(file path): Writes at most 1MB of binary data from a file to the response of a remote script. Returns 1 on success and 0 on failure.

• trendgraph_restart(trendgraph_alias) : Clears the trend graph identified by trendgraph_alias and begins sampling.

  trendgraph_restart("my_graph")

• trendgraph_stop(trendgraph_alias, clear = 0) : Stops the trend graph identified by trendgraph_alias and optionally clears the trend graph according to the clear flag (default 0).

  trendgraph_stop("my_graph")
  trendgraph_stop("my_graph", 1)

Functions to convert between data types.

• bytes_to_float("variable1", "variable2", "variable3", "variable4") : Assembles a floating point value from the provided byte variables. variable1 is the least significant byte and variable4 is the most significant byte. variables are case-sensitive and must be enclosed in double quotes. Example: float_to_bytes(3.14, "a", "b", "c", "d");result = bytes_to_float("a", "b", "c", "d") ⇒ result will contain the value 3.14.
• float_to_bytes(floatValue, "variable1", "variable2", "variable3", "variable4") : Decomposes a floating point value into its composed bytes. Afterward the bytes can be manipulated in various ways to, for example, change the byte order and store the values in addressable internal memory. variable1 is the least significant byte and variable4 is the most significant byte. variables are case-sensitive and must be enclosed in double quotes.

• select_if(conditional_expression, Value1, Value2): Returns value1 if conditional_expression is true, or value2 if conditional_expression is false.
• select_case (default_value, conditional_expression_1, value_1, conditional_expression_2, value_2, conditional_expression_3, value_3, …): Arguments are evaluated sequentially. If conditional_expression_1 is true, value_1 is returned. Else, if conditional_expression_2 is true, value_2 is returned. Else, if conditional_expression_3 is true, value_3 is returned, etc. If none of the conditional expressions are satisfied, default_value is returned. value_{index} arguments may can be strings, but in that case, they must all be strings.
  (Example 1) select_case (1000, a>5, 100, $b==” APPLE”, 200) ⇒ 100 is returned if a is greater than 5, 200 is returned if the value of the internal string variable $b is “APPLE”, and 1000 is returned if neither case is true.
  (Example 2) select_case (“NORMAL”, temp>100, ”HOT”, temp<0, ”ICE”) ⇒ If temp is greater than 100, “HOT” is returned, and if temp is less than 0, “ICE” is returned. If neither condition is true “NORMAL” is returned.
• select_by_key(default_value, key_expression, key_1, value_1, key_2, value_2, key_3, value_3, …) If key_expression is equal to 2, value_2 is returned, if key_expression is equal to key_3, value_3 is returned, etc. (The return value, default_value, and value_{index} can be strings, but in that case they must all be strings.
  (Example 1) select_by_key(-1,a+b,10,100, 20,200, 30,300) ⇒ If a+b is 10 100 is returned, if it is 20 200 is returned, if it is 30 300 is returned, otherwise -1 is returned.
  (Example 2) select_by_key(0, $a+$b,”ONE”,1 ,”TWO”,2 , “THREE”,3) ⇒ If $a+$b is “ONE” 1 is returned, if “TWO” 2 is returned, if “THREE” 3 is returned, otherwise 0 is returned.
  (Example 3) $a=select_by_key(“NOTHING”, a+b,1,”ONE” ,2,”TWO”, 3,“THREE”) ⇒ If a+b is 1 “ONE” is returned, if it is 2 “TWO” is returned, if it is 3 “THREE” is returned , otherwise “NOTHING” is returned.
• select_by_index(default_value, index_expression, start_index, value_1, value_2, value_3, …) If index expression evaluates to the start index value_1 is returned, if index_expression evaluates to start index + 1 value 2 is returned, if index_expression evaluates to start_index + 2 value_2 is returned, etc. Otherwise, default_value is returned. (The return value, default_value, value_{index} can be strings, but in that case, they must all be strings)
  (Example 1) var = select_by_index(-1,a,5,100,200,300) ⇒ If a is 5 100 is returned, if 6 200 is returned, and if 7 300 is returned. Otherwise -1 is returned.
  (Example 2) $result = select_by_index(“NOTHING”,a,5,”A”,”B”,”C”)⇒ If a is 5 “A” is returned, if a is 6 “B” is returned, If a is 7, “C” is returned, otherwise “NOTHING” is returned.

Functions associated with the system.

• action_group_repeat_index() : Retrieves the number of times a user event was executed.
• backlight_state(): Returns whether or not the LCD backlight is on. 1 for on, 0 for off.
• beep(): Causes the panel PC to emit an audible beep sound.
• bitwise_not(value): Returns the binary complement of value.
• change_screen(screen_number): Transitions to the screen identified by screen_number.
• cpu_usage() : Returns the current CPU utilization as a percentage. This function always returns 0 when running in the simulator or on a PC.
• enable_modbus_batching(enable = 1): Enables or disables the Modbus optimization feature that batches adjacent Modbus addresses into a single Modbus query. The feature is enabled by default and is recommended for best performance, but there are limited situations where it may not be needed, such as a device that only supports processing one address per query. In such a case, enable_modbus_batching(0) can be used to make the Modbus queries compatible. Typically this function does not need to called. The enable argument is optional and defaults to 1.
• exit_project(): Causes the current project to exit. This is the same effect as touching the upper right corner of the screen 5 times in quick succession.
• enable_status_monitoring(enable = 1): Enables status monitoring messages to appear overlaid on the panel PC's screen. The enable argument is optional and defaults to 1.
• free_memory_bytes(): Returns the amount of free system memory in bytes. This function always returns 0 when running in the simulator or on a PC.
• firmware_version() : Retrieves the firmware version running on the panel PC. For example 273 corresponds to v2.73.
• idle_seconds() : Returns the number of seconds since the screen was last touched.
• idle_minutes() : Returns the number of minutes since the screen was last touched. Note: Calling set_backlight_state(1) will reinitialize the idle timer.
• is_pc(): Returns 1 if the project is currently running on a PC or 0 if not.
• is_status_monitoring_enabled(): Returns 1 if status monitoring is enabled or 0 if it is not enabled.
• keypad_state(): Returns whether the current keypad is opened. 1 if opened, 0 if not.
• keypad_text(): Returns the most recently entered keypad value as text. This function applies to both numeric and alpha-numeric keypads.
• keypad_text_length(): Returns the length of the string returned by keypad_text().
• keypad_value(): Returns the most recently entered keypad value.
• prev_screen_id() : Returns the id of the screen that the current screen navigated from.
• queries_per_sec() : Returns the number of external device queries sent per second.
• rand() : returns a random number in the range of 0~32767 (0x7FFF)
• reboot_system() : Reboots the panel PC. This function is not supported when running in the simulator or on a PC.
• restore_field_resource_color (resource number): Restores the color field resource to the original color set by the editor. Example) restore_field_resource_color(3)
• scale(input, minimum input, maximum input, minimum output, maximum output) : Scales input proportionally to (maximum input - minimum input) / (maximum output - minimum output).
• screen_id() : Returns the id of the current screen.
• self_ip_addr() - Returns the IP address of the panel PC as a string (for example: 192.68.0.50). Note: This function returns a null string when running in the simulator or on a PC.
• set_backlight_state(value): Sets the state of the LCD backlight on or off. If value is 1 the LCD backlight turns on, if value is 0 the LCD backlight is turns off.
• set_data_processing_period(value) : This function can be used to throttle CPU usage. If the CPU usage for a project is too high, the data processing period can be increased to throttle back the amount of resources that the HMI software dedicates to processing data. value is in units of milliseconds. This function can be useful when the CPU utilization increases due to an increase in the number of events or actions in the project. Typically, it would only be called once at the start of a project, but it can be called multiple times in a project to adjust the CPU utilization dynamically. Setting this value to 0ms will cause the data processing to run as fast as possible, but will also cause the highest CPU utilization. Values below 50ms should be used with caution. If the CPU utilization is approaching 100%, set this value to approximately 100ms, and the communication interval to 30ms as a reasonable starting point. Beginning with firmware v3.87, this value defaults to 50ms. In prior versions the default is 0ms.
• set_field_resource_color(resource number,R,G,B) : You can change the color of color field resource in real time. (Caution: Only predefined colors can be changed in the editor.) Ex) set_field_resource_color(3,255,0,0) Changes color resource number 3 to red.
• set_modbus_word_write_always_multi(active_status_flag = 1): When active_status_flag is `1` or omitted, this function causes all Modbus register (16-bit word) writes to use function code 16 (Write Multiple Registers) even when the number of registers to write is 1.
• set_viewer_browser_title(title): Sets the title of the web browser so the desired text appears in the title bar of the web browser when using the remote viewer from a web browser.
• srand(seed) : Sets the seed value for generating random numbers with the rand() function. It is recommended to call srand(tick_count()) to seed the random number generator before using rand().
• start_action_group(action_group_name): Executes the action group identified by action_group_name.
• status_monitoring_message(): Returns the current status monitoring message.
• tick_count() : The number of milliseconds since the system was powered on. This is a 32-bit millisecond timer that will overflow every 49.7 days.
• touch_duration() : The number of milliseconds since the last time the screen was touched. If the screen has never been touched -1 is returned.
• verify_developer_key(value) : Using the ComfileHMI panel PC's runtime configuration screen, a unique key can be assigned to a individual device or group of devices. verify_developer_key can then be used at runtime within a project to test which device a project is running on and dynamically offer a different experience. The developer key cannot be read; one can only check if value matches the developer key assigned to the device. This function returns 1 if the value matches the developer key assigned to the device or 0 if it does not. This feature is only supported on PCs with a software licensing USB dongle. Whether or not this function is supported in the simulator is determined by runtime settings. The PC runtime verifies the given value against the developer key registered to the USB licensing dongle. The developer key can be registered to the USB licensing dongle from within the simulator or PC runtime settings.

In the Add Action –> Run Action Group properties, in the Advanced Options is the ability to pass a primary and secondary parameter to the actions (Add Action Parameter and Add Secondary Action Parameter respectively) .

The parameters can then be read from within the executing action using the following functions.

• action_param : Retrieves the primary parameter passed to an action.
• sub_action_param : Retrieves the secondary parameter passed to an action group.

Functions with no argument.

• year() : The current year
• month() : The current month (1~12)
• day() : The day of the month
• day_of_week() : The day of the week (0~6), 0 = Sunday
• hour() : The hour of the day (0~23)
• minute() : The minute component of the current hour (0~59)
• second() : The second component of the current minute (0~59)
• last_day_of_month(year, month) : returns the last day of the given month for the given year

Functions that take 1 argument but return no value.

• set_year(value) : Sets the current year
• set_month(value) : Sets the current month (1~12)
• set_day(value) : Sets the day of the month
• set_hour(value) : Sets the hour of the day (0~23)
• set_minute(value) : Sets the minute component of the current hour (0~59)
• set_second(value) : Sets the second component of the current minute (0~59)

The following functions be used in the {expression} part of the ComfileHMI's Web API.

• vars_to_json(variable_names) : Returns the values of the supplied variable_names in JSON format. vars_to_json("a|b|$c")
• mem_to_json(start_address, length, decimal_places = 6) : Returns length values for the internal memory starting at start_address with decimal_places decimal places in JSON format. mem_to_json(10,3) will return values for internal memory at addresses 10, 11, and 12, with 6 decimal places.
• filenames_to_json(directory_paths): Returns the list of files in JSON format from the directories specified by directory_paths. Multiple paths are separated by a |. filenames_to_json("storage card\logs|storage card\data1") returns the list of files in both the storage card\logs directory and the storage card\data1 directory.
• dirnames_to_json(directory_path) : Returns the list of subdirectories in JSON format from the directories specified by directory_path. The format of the response is the same as filenames_to_json but the result only includes subdirectories.
• last_http_status_code(): Returns the integer HTTP status code from the last received HTTP response.
• last_json_result() : Returns a success or fail result of the most recent query. 1 for success; 0 for failure. For example, if there is a syntax error in the query, the password does not match, or non-existent file path is submitted, 0 is returned.
• last_json_error_code() : Returns the numeric error code of the most recent query.
• last_json_error_message() : Returns the error message of the most recent query.

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