FX ES Original Series Models

All FX ES Original Series Models

These are confirmed to be working on the 82ES, 83ES, 85ES, 570ES and 991ES Models

Rectangular to Polar Coordinates Oversight

This oversight serves as the basis to the below glitches. It relies on a bug that exists in the replay memory history which causes the results of the previous equation to instead appear in the editable area. It involves placing the radius "r" character within the editable area in COMP mode of which is it not designed for and therefore points to an unexpected memory address.

1. Calculate Pol(0,1).
2. Type a stack of 6 fractions.
3. Go the very last fraction line at the bottom and press 1 and then the 𝑥☐ key.
4. Press = -> AC -> Up -> AC -> Left.
5. Delete the "1" and the results of the Polar equation is now within the editable area including "r"

Screen corruption

This causes the screen to corrupt before the CPU stops driving the LCD (Presumably due to corrupted registers, causing a single line to display) and powers off. The glitch causes the integrity check to fail, resulting in an automatic factory reset upon boot.

1. Obtain r in COMP mode using the Rect to Polar oversight.
2. Execute 1⁄1r. This causes the stack pointer to become corrupted, moving memory writes to an unexpected area.
3. Press Abs 5 times.
4. Press √□ 8 times.

Invalid Norm Mode

This uses r to corrupt the Norm output format mode, causing the resulting output to be glitchy. This remains until Norm mode is changed or the calculator setup is cleared. Answers will show up as glitch characters, may be blank or give out strange results which may change when the S⇔D key is pressed.

1. Obtain r in COMP mode using the Rect to Polar oversight.
2. Execute 1:r.
3. Press = twice.
4. Press MODE and Enter TABLE mode.
5. Press ON

Glitched ERROR Screen

1. Obtain r in COMP mode using the Rect to Polar oversight.
2. Enter a fraction before r for 1⁄1r. Press M+. You will get Syntax ERROR. Press AC.
3. Keep pressing cos. The screen will suddenly changed to a glitched screen with ERROR printed. The values may change if sin or tan are used.

Diagnostics Mode Subroutine

1. Obtain r in COMP mode using the Rect to Polar oversight.
2. Execute 1⁄1r. Then press AC.
3. Press (-) and the D variable in an alternating pattern until the cursor turns into a block.
4. Press √□ The calculator will enter diagnostics mode. Pressing AC on the TEST OK Screen will corrupt the text and the calculator will crash.

This glitch is potentially a form of ROP on the Non-Plus models.

FX-82ES, FX-83ES and FX-85ES Only

These are confirmed to be working on the 82ES, 83ES, 85ES models.

FX-991ES/570ES Upgrade Exploit

This involves using r corruption to overflow the editable area, allowing writes to unintended parts of RAM, which in this instanced changes the P mode.

1. Obtain r in COMP mode using the Rect to Polar oversight.
2. Press M+ with the following: √□ r then press AC.
3. Press Ans 10 times
4. Press Log■□. The screen will start to corrupt. In the lower box press Abs. In the upper box press ( 10 times.
5. Press = and then Left
6. Move the cursor to the right of the Abs symbol that was placed and press sin 7 times. Press = and Left.
7. Move the cursor into the Abs box and press ( 7 times. Press = and Left.
8. Move the cursor to the left of the Abs symbol. Press ( 6 times. Press = and Left.
9. Press ( 7 times, then press = and Left. Repeat this step 5 more times.
10. Press ( 5 times, the screen will go blank.
11. Press AC and then Press Shift 9 1 and = to Clear the Setup.
12. Repeat the same but Clear the Memory.
13. The contrast value has been corrupted and will change the screen contrast once an equation is performed. Press Shift SETUP to go into the Setup menu. Press Down and 6 to change the contrast. Pressing Left a few times will fix the contrast.
14. The calculator is now in 991ES mode which can be confirmed by pressing the MODE Key. The screen memory corruption effect is still in place however, and the calculator will reset after ON is pressed as this exploit causes the integrity check to fail.