WARNING: Invoking the tests described below may result in the clearing of data memory, program memory, and mode settings.

The DS-834 has built in display and keyboard tests. The test menu is accessed by pressing 2nd, then RESET (the reset menu is displayed), then simultaneously pressing the 2nd key, the (-) (change sign) key, and the DEL key. The first two options of the test menu are displayed: "TEST:1)D2)K". The third option is displayed after pressing the right cursor key: "3)LOOP".

Display test. Press 1 to access the display test. Press ENTER repeatedly to cycle through the three different test patterns. Press DRG to abort the display test and return to the test menu.

Keyboard test. Press 2 to access the keyboard test. Forty-eight columns of pixels on the top line are displayed. Unlike many other keyboard tests, the keys do not need to be pressed in any particular order. As each key is pressed, a column of pixels is turned off. The keyboard test is complete when all pixel columns are turned off. Then press ENTER to return to the test menu.

Looping display contrast test. Press 3 to access the display contrast test. The calculator automatically cycles through the display contrast settings with all pixels energized until the test is interrupted by pressing DRG. After interrupting this test, the test menu is redisplayed.

From the test menu, press ENTER to return to the reset menu.

(Based on several factors, including model information etched on the PCB of this calculator, I believe this calculator is manufactured by Kinpo Electronics, Inc., and is functionally identical to the Kinpo SR19S1/Citizen SRP-285II.)

WARNING: Invoking the tests described below may result in the clearing of data memory, program memory, and mode settings.

The DS-883 has built in display, memory and keyboard tests. The test menu is accessed by pressing MODE, then selecting the RESET (or pressing 7) menu option, then selecting the RESET menu option (or pressing 2) from the "RESET" submenu (the the reset menu is displayed), and then simultaneously pressing the 2nd key, the and the (-) (change sign) key. A menu of test options is presented.

     ****TEST****
     1LCD  2KEY
     3CONT 4RAM

LCD test. Press 1 to access the display test. Press EXE repeatedly to cycle through the three different test patterns. Press EXIT to abort the display test and return to the test menu.

KEYboard test. Press 2 to access the keyboard test. A pattern of 54 dashes that looks similar to the keyboard layout is displayed. Unlike many other keyboard tests, the keys do not need to be pressed in any particular order. As each key is pressed, a dash is turned off. The keyboard test is complete when all dashes are turned off. Then press EXE to return to the test menu.

Looping display CONTrast test. Press 3 to access the display contrast test. The calculator automatically cycles through the display contrast settings with all pixels energized until the test is interrupted by pressing EXIT. After interrupting this test, the test menu is redisplayed.

RAM test. Press 4 to access the RAM test. The RAM test page is displayed and the test starts automatically.

     RAM CHECK
     32kbyte

After about three seconds, the test is complete, and "- O K -" is displayed at the bottom of the screen for another couple of seconds. The calculator resets itself and returns to the main menu.

To exit the test menu without performing the RAM test or doing a reset, press EXE to return to the reset submenu. From the reset submenu, press MODE, and then 0 (the "0MAIN" option) to get back to the main calculation menu.

(I believe this calculator is manufactured by Kinpo Electronics, Inc., and is functionally identical to the Kinpo SG2/Citizen SRP-400G.)