SF-7100SY SF-7200SY

Users Guide
GUIDELINES LAID DOWN BY FCC RULES FOR USE OF THIS UNIT IN THE U.S.A. (not applicable to other areas).

NOTICE

This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. This equipment generates, uses and can radiate radio frequency energy and, if not installed and used in accordance with the instructions, may cause harmful interference to radio communications. However, there is no guarantee that interference will not occur in a particular installation. If this equipment does cause harmful interference to radio or television reception, which can be determined by turning the equipment off and on, the user is encouraged to try to correct the interference by one or more of the following measures: Reorient or relocate the receiving antenna. Increase the separation between the equipment and receiver. Connect the equipment into an outlet on a circuit different from that to which the receiver is connected. Consult the dealer or an experienced radio/TV technician for help.

FCC WARNING

Changes or modifications not expressly approved by the party responsible for compliance could void the users authority to operate the equipment. Proper connectors must be used for connection to host computer and/or peripherals in order to meet FCC emission limits. Connector SB-63. SF-7100SY/7200SY to SF-5590SY/5790SY/5990SY/ 6500SY/6700SY/6900SY/7100SY/7200SY Connector FA-128. SF-7100SY/7200SY to PC Declaration of Conformity SF-7100SY/7200SY CASIO COMPUTER CO., LTD. CASIO, INC. 570 MT. PLEASANT AVENUE, DOVER, NEW JERSEY 07801 973-361-5400
Model Number: Trade Name: Responsible party: Address: Telephone number:
This device complies with Part 15 of the FCC Rules, Operation is subject to the following two conditions: (1) This device may not cause harmful interference, and (2) this device must accept any interference received, including interference that may cause undesired operation. CASIO COMPUTER CO., LTD. assumes no responsibility for any damage or loss resulting from the use of this manual. CASIO COMPUTER CO., LTD. assumes no responsibility for any loss or claims by third parties which may arise through the use of the Digital Diary. CASIO COMPUTER CO., LTD. assumes no responsibility for any damage or loss caused by deletion of data as a result of malfunction, repairs, or battery replacement. Be sure to back up all important data on other media to protect against its loss.
Before using the Digital Diary for the first time.
Use the following procedure to load batteries before using it for the first time. 1. Slide the battery switch on the back of the Digital Diary to the REPLACE BATTERIES position. Battery switch

NORMAL OPERATION

REPLACE BATTERIES
2. Pressing down at the points marked (A) in the illustration, slide the battery compartment cover in the direction (B) to remove it. (A) (B)
3. Load two new batteries, making sure that their positive (+) and negative () ends are facing correctly.
4. Close the battery compartment cover. 5. Slide the battery switch back to the NORMAL OPERATION position.
2 6. Pull the insulating tape from the back-up battery by pulling in the direction indicated by the arrow.

Important!

Be sure to load the main batteries before removing the insulating tape from the back-up battery.
7. Press ON/OFF to turn power on.
After about two seconds, the Home Time screen appears. 8. Press FUNCTION, select Time set, and then use the procedure on page 20 to set the Home Time. If you turn power off without setting the Home Time, the SET TIME! message appears the next time you turn power on. The Digital Diary will not operate properly until you set the Home Time.
Turn on the Digital Diary at least once a month to check the current condition of the batteries.

Getting Started

Make sure you read this part of the manual.

General Guide

Display
Mode keys Cursor keys Number keys Scroll/Search keys
ON/OFF key SYNCHRONIZE key LIGHT key ESC key Connector terminal

Display Change key

Alpha keyboard

FUNCTION key

I Display
When lighting is dim, you can turn on an EL (electro-luminescent) backlight for easier viewing.
To turn on the EL backlight
There are two ways to turn on the backlight of the display. Pressing LIGHT causes the backlight to turn on for about 15 seconds, and then turn off automatically. Pressing SHIFT and then LIGHT also turns on the backlight, but in this case the backlight stays on as long as you keep performing key operations on the Digital Diary. The backlight turns off automatically if you do not perform any key operation for about 15 seconds. Leaving the backlight on for long periods greatly reduces battery life! You can manually turn the backlight off by pressing LIGHT again. Failure of the backlight to turn on indicates low battery power. Replace batteries as soon as possible. Display Indicators
SHIFT CAPS CODE NEW/EDIT INDEX DATA SNOOZE DAILY KEY

0 q w e

1 Low battery warning 2 Memory locked 3 Telephone Directory Mode 4 Memo Mode 5 To Do Mode 6 Reminder Mode 7 Schedule Keeper Mode 8 Calendar Mode 9 Expense Manager Mode 0 Home Time/World Time Mode q Calculator Mode w Conversion Modes
e Game Modes r Indicates data above t SHIFT key operation y Upper-case input u CODE key operation i NEW/EDIT screen o Index display p Data display a Snooze feature activated s Daily alarm on d Key sound on f Indicates data below

I All-Reset

Use the following procedure to reset the unit to its initial settings.
Do not use a very sharp pencil or other object to press the RESET button. Perform the reset operation only after main batteries and back-up battery are correctly installed.
To start the all-reset operation
1. Turn power off. 2. Press the RESET button on the back of the Digital Diary with a thin, pointed object.
3. Now you should press Y for yes or N for no in accordance with the conditions described below. When to press Y for yes When you want to reset the unit and clear all data and settings. When you are resetting the unit after a data error (page 76). 1. Press Y in response to the message that appears on the display when you start the all-reset operation.

12 2. Press ENTER to reset the Digital Diary or ESC to abort. After pressing ENTER, the message shown below appears to indicate that RESET is being performed. RESET takes about 10 seconds to complete.
After the reset procedure is complete, the message SET TIME! appears. After about two seconds, the Home Time screen appears. 3. Press FUNCTION, select Time set, and then use the procedure on page 20 to set the Home Time. If you turn power off without setting the Home Time, the SET TIME! message appears the next time you turn power on. The Digital Diary will not operate properly until you set the Home Time. When to press N for no When you are not resetting the unit to clear all data and settings. When you are not resetting the unit after a data error (page 76). 1. Press N in response to the message that appears on the display when you start the all-reset operation. At this time, the message CHECKING DATA, PLEASE WAIT. appears. After the data check procedure is complete, the message SET TIME! appears. After about two seconds, the Home Time screen appears. 2. Press FUNCTION, select Time set, and then use the procedure on page 20 to set the Home Time. If you turn power off without setting the Home Time, the SET TIME! message appears the next time you turn power on. The Digital Diary will not operate properly until you set the Home Time. Following are the initial settings of the unit after you perform the all-reset operation. Home Time: New York JAN 1, 2000 (SAT) 12:00 AM 12-hour format World Time: London Daily Alarm: 12:00 AM Sound: Daily alarm OFF Key ON Messages: English Character input: CAPS ON

I Power Supply

Your Digital Diary is powered by two AA-size alkaline batteries, and its memory is protected by a single CR2032 lithium battery.

Low Battery Warning

Failure of anything to appear on the display after you turn on power or appearance of the low battery message, MAIN BATTERIES WEAK! REPLACE THEM! UNIT WILL NOT TURN ON AGAIN! (followed by the display turning off in about 10 seconds) normally indicates that main battery power is low. Note, however, that pressing the RESET button on the back of the unit and then performing steps 1 and 2 of the procedure under When to press N for no above can sometimes restore normal operation. When the low battery message appears on the display even if you perform these steps, it means you should replace the main batteries as soon as possible.
Take care that you do not make a mistake and delete memory contents at this time.
Replace batteries only when low battery power is indicated by failure of the Digital Diary to turn on when you press the ON key. Do not replace batteries as long as the Digital Diary turns on normally when you press the ON key. There is not low battery warning for the back-up battery. Be sure to replace the back-up battery once every 5 years. Be sure you keep a separate copy of all important data that you store in the Digital Diary.

4. Remove both old batteries and replace them with new ones. Make sure that the positive (+) and negative () ends are facing correctly. 5. 6. 7. Close the battery compartment cover. Slide the battery switch back to the NORMAL OPERATION position. Press ON to turn power on. This causes the message SET TIME! to appear. Be sure to set the time again at this time. The Digital Diary suspends its clock operation while replacing batteries.
8. Press FUNCTION, select Time set and then use the procedure on page 20 to set the time. 15
To replace the back-up battery
Do not remove the back-up battery from the Digital Diary while the main batteries are removed or the low battery message appears on the display. Be sure to replace the back-up battery at least once every 5 years. Otherwise, you run the risk of losing data stored in memory.
1. Press OFF to turn power off. 2. Remove the screw that holds the back-up battery compartment cover in place and open the cover.
3. Insert a thin, pointed object into (A) and remove the old battery.
4. Load a new battery into the compartment, making sure that its positive side is facing up (so you can see it). 5. Replace the battery compartment cover and secure it with its screw. Take care that you do not overtighten the screw.
If nothing appears on the display when you turn on power, it means that the main batteries are low. Replace the batteries (page 13).

Auto Power Off Function

The unit automatically turns power off if you do not press any key for about three minutes. Any alarms you set still sound, even if power is turned off.

I Function Menus

Pressing FUNCTION displays a function menu, whose contents differs depending on the mode. Pressing SHIFT FUNCTION displays a function menu of general system settings (system function menu). Input the number of the left of the function you want to use to select it. To exit from a function menu, press ESC.

I System Language

Your Digital Diary is capable of producing messages in any one of five languages (English, German, Spanish, French, Italian).
To select the system language
1. 2. Press SHIFT FUNCTION and then select Language. Press the number key that corresponds to the language that you want to use. To select English, you would press 1. The system language automatically changes to English whenever you perform the RESET operation (page 11) or after data files are restructured (page 14).

To change a World Time zones settings
1. In the World Time Mode, display the zone you want. 2. Press FUNCTION. 3. Switch between 12/24 hour (page 21), switch between standard and daylight saving time (page 21), and set the date format (page 21). Timekeeping format and date format settings are applied to all World Time zones and to the Home Time Mode. The standard/daylight saving time setting is applied to the currently selected time zone only. See page 24 for details on using the Zone Change function menu item.
I Zone Information Screen
The zone information screen shows the name of a major city and the time difference from your Home Time for each World Time zone.
To display the zone information screen
In either the World Time Mode or Home Time Mode, press DISP CHNG to change to the zone information screen for the displayed zone. Time difference from your Home Time zone City in zone
To exit the zone information screen, press DISP CHNG, ESC, or HOME/ WORLD.
To change zone information screen content
If you change the city name of the zone information screen, the name you input will also appear on the Home Time and World Time screens. 1. 2. 3. In the World Time Mode, display the zone you want. Press FUNCTION and select Zone change. Change the contents of the screen. Use H and J to move the cursor. You can input up to 13 characters for the city name.
4. After you make changes, press ENTER. At this time the message Are you sure (Y/N)? appears. 5. Press Y to store your changes or N to abort.

City List

Time Difference + 00 + 01 + 02 + 03 + 04 + 05 + 06 + 07 + 08 + 09 + 10 + 11 + 12 + 13 + 14 + 15 + 16 + 17
City Name Midway Honolulu Anchorage Los Angeles Denver Chicago New York Santiago R. de Janeiro F. de Noronha Azores London Rome Jerusalem Moscow Abu Dhabi Karachi Dhaka Bangkok Hong Kong Tokyo Sydney Noumea Auckland

Other Cities in Zone

San Francisco, Seattle, Las Vegas El Paso Dallas, Mexico City, Houston Washington D.C., Boston, Montreal Caracas Sao Paulo, Buenos Aires
Greenwich Mean Time Paris, Madrid, Amsterdam, Berlin Cairo, Athens, Helsinki, Beirut Jeddah, Kuwait, Nairobi Dubai
Jakarta, Hanoi Beijing, Taipei, Singapore, Manila Seoul, Pyongyang Guam Port Vila Wellington
The time difference values in the above table are what would appear when New York is set as the home time.

Data Bank Operations

This part of the manual tells you how to input and edit text, and how to protect your personal data with a password.

I Inputting Text

Input or correction is performed at the current cursor location.
About data items and entries

Data item

The above shows a typical Telephone Directory data item, which is made up of a number of entries. When you are inputting data, prompts appear on the display to tell you what entry needs text input.

To move the cursor around the screen

Use K, L, H, and J.

The maximum number of characters you can input for each data item is 511, including newline symbols and separator marks (page 27).
To input letters and numbers
Press the key that is marked with the letter or number.
To input upper-case letters
Press CAPS to switch between upper-case and lower-case letters. The CAPS indicator shows the keyboard is shift-locked for upper-case letters.

To shift the keyboard

Press SHIFT to temporarily shift the keyboard. The indicator SHIFT on the screen shows that the keyboard is shifted. If the keyboard is set for upper-case letters (by the CAPS key), pressing SHIFT changes to lower-case. As soon as you input one character, the keyboard unshifts.
To input punctuation marks and other symbols
Press CODE and then any key marked with the punctuation or symbol you want to input. The CODE indicator shows that the CODE key was pressed.
To input accented characters
Example: To input CODE W E
Newline symbols and separator marks
Each press of B inputs a newline symbol ( ). Dont confuse the newline symbol with the separator mark ( ), which is automatically added at the end of data that you are inputting when you press ENTER to advance to the next entry. Separator marks are not shown when you recall data.
To change one character to another
1. Move the cursor to the character you want to change. 2. Input the character you want to change to.

To delete a character

1. Move the cursor to the character you want to delete. 2. Press DEL.

To insert characters

1. Move the cursor to the location of the insertion. 2. Press INS. Each press of INS opens up a space at the cursor location. 3. Input the characters you want in the space.
I Inputting Dates and Times

General

Use the cursor keys to move the cursor. 27

3. Press the number key that corresponds to the entry you want to appear on the index display. The unit changes back to the index display showing the data you specified.

I Record Summary

The record summary provides an overview of each Telephone Directory file.

File title

Number of records stored
To display the record summary
In the Telephone Directory Mode, press FUNCTION and then select Record summary. Press ESC to return to the original Telephone Directory Mode display.

Memo Mode

Memo data is stored in the sequence it is input, without sorting.

To enter the Memo Mode

1. Press MEMO to display the initial Memo Mode screen. Number of records stored in area File title
Memory usage Initial prompt 2. Press MEMO again to change to another Memo Mode file. Each press of MEMO changes the file in the following sequence. MEMO-1 MEMO-2 MEMO-3

To input Memo Mode data

1. Use MEMO to display the initial screen of a Memo Mode file. 2. Input the first line and press B. A newline symbol is inserted and the cursor goes down to the next line. 3. Input the rest of your memo. 4. Press ENTER to quit and return to the index display (page 28).
Use the same procedure as that described for changing a Telephone Directory file title on page 29.
The record summary provides an overview of each Memo Mode file.
In the Memo Mode, press FUNCTION and then select Record summary. Press ESC to return to your original Memo Mode display. 31

Calendar Mode

The Calendar displays calendars from January 1901 through December 2099. Pressing SCHEDULE in the Calendar Mode enters the Schedule Keeper Mode for the date selected on the Calendar Mode Screen. If the date cursor is located at a date that includes Reminder Mode data, pressing REMINDER enters the Reminder Mode for that date.
To enter the Calendar Mode
Press CALENDAR. Morning appointment Current date (flashing)
Highlighted date Afternoon appointment Week/Day/Remaining days
The current date (according to the Home Time setting) is selected by the date cursor.
I Maneuvering Around Calendars
The following describes the basic operations for maneuvering around the calendars. Use K, L, H and J to move the date cursor. Holding down any of these keys moves the date cursor at high speed. Press to move the date cursor to the first of the previous month, and to move to the first of the following month.

Marker (current setting) 3. Use K and L to move the pointer to the expense type you want to change, and then use H and J to change the setting. Expense types set to Yes appear in the index display, while those set to No do not. 4. After you are finished, press ENTER to return to the index display.

I Payment Type Labels

Payment type data includes a label that appears on the screen whenever you display the expense data. To change these labels, use the procedure under To change expense type labels and icons on page 45. The only difference is that you select Payment types in step 2, and you skip steps 5 through 7 (because there are not payment type icons).

I Exchange Rate

The expense total in the periodic report is multiplied by the exchange rate value to produce the Converted item amount.

To set the exchange rate

1. Press EXPENSE to display the initial Expense Manager Mode screen. 2. Press FUNCTION and then select Exchange rate. Current setting
3. Input an exchange rate. The exchange rate can have an integer part up to 12 digits and a decimal part up to 12 digits. 4. Press ENTER to quit.
I Periodic Expense Report
The following procedure produces an on-screen report of all your expenses.
To produce a periodic expense report
1. Press EXPENSE to display the initial Expense Manager screen, and then press K, L, , or to change to the index display. 2. Press FUNCTION and then select Report. 3. Input the starting date and the ending date and then press ENTER. Pressing ENTER produces an expense report like the one shown below.
4. Use and to change screens to view other. 5. Press ESC to return to the Expense Manager Mode initial display.
The record summary provides a quick view of how many data items are stored in each Expense Manager file.
In the Expense Manager Mode, press FUNCTION and then select Record summary. Press ESC to return to your original Expense Manager Mode display. 49

Searching for Data

This section explains everything you need to know about searching for and recalling data.

I Scroll Search

Scroll search can be used in the Telephone Directory, Memo, Schedule Keeper, To Do, and Expense Manager modes.
To recall data using scroll search

To access protected modes
1. 2. Turn on Digital Diary power. Press the mode key for one of the protected modes. INPUT PASSWORD appears on the display. If you were in a protected mode the last time you turned power off, INPUT PASSWORD appears as soon as you turn on the Digital Diary.
3. Input the correct password and press ENTER. If you input the wrong password, the password input screen remains on the display. Once you input your password, you will not have to input it again, even if you exit a protected mode and then re-enter it later. Your password input remains valid until you turn the Digital Diary off or until you manually lock memory (page 57).

To change the password

1. Turn on the Digital Diary. INPUT PASSWORD appears on the display. 2. Input the correct password and press ENTER.
3. Press SHIFT FUNCTION and then select Password.
4. Select Modify password, which causes the currently registered password to appear. 5. Make any changes to the password you want, and then press ENTER to store the new password.

To delete the password

1. Turn on the Digital Diary. INPUT PASSWORD appears on the display. 2. Input the correct password and press ENTER. 3. Press SHIFT FUNCTION and then select Password. 4. Select Delete password, which causes a confirmation message to appear asking if you really want to delete your password. 5. Press Y to delete or N to abort. After you delete the password data, protected modes can be viewed by anyone.
To lock memory without turning power off
1. While using the Digital Diary after you have input your password, press SHIFT FUNCTION and then select Password. 2. Select Lock system. Now when you try to enter another protected mode, the password input screen appears and you will have to input your password again.

Conversion Modes

Your Digital Diary actually gives you two conversion modes, one for metric conversion and one for currency conversion.
To enter the Conversion Modes
1. Press CONV/GAME to display the initial Unit Conversion Mode screen. Unit Conversion direction Equivalent (1 inch = 2.54cm)
Input/result area 2. Press CONV/GAME again to change to the Currency Conversion Mode (page 59) and display the initial Currency Conversion Mode screen. Currency Conversion direction Equivalent

Input/result area

I Metric Conversions
All conversion values in this mode are preset and cannot be changed. inches centimeters miles kilometers knots kilometers/h US tons kilograms ounces grams UK gallons liters calories joules Celsius Fahrenheit yards meters feet yards UK tons kilograms pounds kilograms carats grams US gallons liters horsepower kilowatts

To enter the Game Modes

1. Press SHIFT CONV/GAME to display the initial Poker Mode screen. Game over indicator Bet indicator Your points You win indicator

Mode name

Your hand

Bet amount

2. Press M to change to the Blackjack Mode (page 63) and display the initial Blackjack screen. Mode name Game over indicator Bet indicator Your points

I Poker Game

The following describe rules and procedures for playing the poker game.

Poker Game Rules

The game is 5-card draw. Unlike standard poker, you do not play against other players. Instead, you try to accumulate points. The following table shows how many point are awarded for each type of hand.
62 Type of Hand Royal Flush Straight Flush Four of a Kind Full House Flush Straight Three of a Kind Two Pair One Pair (Jacks or better) Bet Bet Bet Bet Bet 100 50
Note that no points are awarded for anything less than a pair of Jacks. The relative value of the cards is meaningless. Two pair always scores the same number of points, regardless of what cards make up the two pair. Before cards are dealt to start each hand, you can change the bet amount to 10, 20, 30, 40, 50. The bet amount cannot be changed once a hand is dealt. The bet amount is automatically deducted from your point total when each hand is dealt. You start with 1,000 points, and the maximum number of points you can accumulate is 999,999. The game ends when your points reach zero or 999,999.

To play the poker game

1. 2. 3. Enter the Poker Mode. Use B to declare the bet amount if you want. Press H to start the game. The first five cards are dealt.
4. Use number keys 1 through 5 to select which cards you want to keep (1 through 5 from left to right). Pressing a number key causes the letter H (for Hold) to appear above the corresponding card. To deselect a card, press its number button again so the H disappears. You can mark anywhere from no cards to all your cards. 5. After you select which cards you want to hold, press H. The unmarked cards disappear and are replaced by new cards, and the hand ends.

1. 2. 3. Enter the Blackjack Mode. Use B to declare the bet amount if you want. Press H to start the game. Two cards are dealt to the player and one to the dealer. The Hit, Stand, and Fold indicators flash on the display, waiting for the players response. In certain cases, the messages Insure or Double may also appear.
4. Press the letter key that corresponds to the operation you want to perform. H: hit S : stand I : insure D: double down Q: fold (surrender) 5. 6. If you draw a card and the total of your cards is still less than 21, repeat step 3. When you dont want any more cards, press S to tell the dealer you want to stand. At this time the dealers hand is completed and the winner is determined. If you win, the Win indicator appears and the number of points based on your hand and the amount you bet are added to your point total (see the table). If you lose, the Win indicator does not appear and your point total remains unchanged.
7. To play the next hand, continue from step 2, above. Repeat the above procedure until you run out of points or until you score 999,999 points.

Calculator Mode

The Calculator Mode provides you with all the tools you need to perform a variety of calculations throughout the day. It also includes a calculation editing feature that lets you recall the steps of a calculation and make changes. Calculator Mode key

Number keys

Cursor keys
Memory keys, operator keys C/AC clears the last value input. Press twice to clear a calculation on the screen and start a new calculation. Use the number keys ( 0 through 9 ) to enter values. Press to input a decimal point. Use !, @, # and $ to specify the arithmetic operation that is marked on each key. = executes a calculation and displays its result. Use MRC, M@, and M+ for calculator memory operations. MRC recalls the content of the memory, and clears it when pressed twice successively. M@ subtracts the currently displayed value from the current memory contents. M+ adds the currently displayed value to the current memory contents. Use % for percentage calculations. Use ^ for square root calculations. !/@ switches the sign of a value between positive and negative.
To correct errors in calculations
If you enter a wrong value, press C/AC once and then enter the correct value. If you press the wrong arithmetic operator key ( !, @, #, $), simply press the correct key before entering anything else.

With this method, you can send all data items stored in the Telephone Directory, Memo, Schedule Keeper, Calendar, To Do, Reminder, or Expense Manager Mode.

Mode Data Items

With this method, you can send all data items stored in specific modes (Telephone Directory, Memo, Schedule Keeper, Calendar, To Do, Reminder, Expense Manager). In the Schedule Keeper Mode, you can send items that appear on the index display (which you specified using the function menus List type item described on page 39).

One Data Item

With this method, you can send one data item stored in the Telephone Directory, Memo, Schedule Keeper, To Do, Reminder, or Expense Manager Mode.
For Calendar Mode data, you can send highlight data. If an alarm (Daily Alarm, Schedule Alarm, or Reminder Alarm) is reached while data is being sent, the alarm does not sound until the data send operation is complete.

To send one data item

1. Display the data display (page 28) of the item you want to send. 2. Press FUNCTION and then select Send record.
3. Input a number 1 or 2 to select the model to which you want to send the data. A message appears asking if you are ready to send. 4. Press Y to start the send operation, or N to abort. To interrupt the send operation at any time, press ESC. After the send operation is complete, the display returns to the screen that was on the display before you started the send operation. Then you can repeat the above procedure to send another item.
To send all data items in specific modes
1. Press SHIFT FUNCTION and then select Send all. Pointer (selected file)
Marker (current setting) 2. Use Kand Lto move the pointer to the mode whose data items you want to send, and then use Hand Jto change the setting. Data in modes set to Yes will be sent, while data in modes set to No will not. 3. Press ENTER. 4. Input a number 1 or 2 to select the model to which you want to send the data. A message appears asking if you are ready to send. 5. Press Y to start the send operation, or N to abort. To interrupt the send operation at any time, press ESC. After the send operation is complete, the display returns to the screen that was on the display before you started the send operation.