Spotlight: Casio fx-3650PII and Comparison with the fx-3650P and fx-50FH (II)
Quick Facts: fx-3650P II
Model: fx-3650P II
Company: Casio
Type: Solar Scientific Algebraic, Programmable with battery backup: 1 x LR44/AP76
Memory: 7 memory registers: A, B, C, D, X, Y, M (M has memory addition and subtraction)
Programming Memory: 390 bytes, 4 program slots
Years in Production: 2013 (per fx-3650PII manual) to Present
Primary Market: Asia
Display: 10 digits
Casio’s fx-3650PII web page: https://www.casio.com/intl/scientific-calculators/product.FX-3650PII/
The fx-3650P II is the successor to the fx-3650P. The interface, menu structure, and the display of the fx-3650PII match that of Casio’s other current dual-powered programmable, the fx-50FH series (current as this blog entry fx-50FHII).
The modes available for the fx-3650 PII are:
COMP: This is our main calculator mode, with all the scientific functions available.
CMPLX: Complex Number mode: features complex arithmetic, conjugate, modulus (Abs), argument, rectangular/polar conversions.
BASE: Base conversions of integers between the four well known bases: binary, decimal, octal, and hexadecimal. The mode contains the standard Boolean operations.
SD: Single variable statistics (formerly named standard deviation mode)
REG: Regressions/two-variable statistics. A is usually the y-intercept and B is the slope.
The regressions available are:
Linear: y = a + b * x
Logarithmic: y = a + b * ln x
e-Exponential: y = a * e^(b* x)
Power: y = a * x^b
Inverse: y = a + b / x
Quadratic: y = a + b * x + c * x^2
ab-Exponential: y = a * b^x
Casio fx-3650P vs Casio fx-3650P II
Both of these calculators are (or were) sold primarily in Asia. They are dual-powered: solar with a backup battery.
Casio fx-3650P
* Years Released: 2002 – about 2013
* Pressing [ e^x ] types e. e(n) takes e^n not e × n.
* Program space: 4 programs, total of 360 bytes
* Absolute value function (Abs) is available in complex number mode (CMPLX) mode only.
The [ MODE ] key:
Page 1: 1: COMP, 2: CMPLX
Page 2: 1: SD, 2: REG, 3: BASE
Page 3: 1: PRGM, 2: RUN, 3: PCL
Page 4: 1: Deg, 2: Rad, 3: Grad
Page 5: 1: Fix, 2: Sci, 3: Norm
Page 6: 1: Disp (display setup, fractions, rectangular/polar in complex mode)
CMPLX (complex numbers, primarily complex number arithmetic)
SD (single-derivation mode, single-variable statistics)
REG (regression mode, two-variable statistics)
BASE (base conversions and Boolean logic)
Program Functions (P-CMD), which is a limited set:
Page 1: ? (prompt), → (store), : (separator), ◢ (output/pause)
Page 2: ⇒ (jump/if-then-else), =, ≠, >, ≥
Page 3: Goto, Lbl
To exit program editing mode, press [ MODE ], [ MODE ], select 2 for RUN
fx-3650 PII
* Production: 2013 – current? (not in United States, but in Asia)
* Pressing [ e^x ] types e^(. This is gives a clear indication that we are using a function (exponential).
* Program space: 4 programs, total of 390 bytes
* Absolute value function (Abs) is available in all modes.
The [ MODE ] key:
Page 1: 1: COMP, 2: CMPLX, 3: BASE
Page 2: 4: SD, 5: REG, 6: PRGM
CMPLX (complex numbers, primarily complex number arithmetic)
SD (single-derivation mode, single-variable statistics)
REG (regression mode, two-variable statistics)
BASE (base conversions and Boolean logic)
The SET UP menu, use arrows to navigate:
Page 1, Angles: 1: Deg; 2: Rad; 3: Gra
Page 2, Fraction: 1: a b/c; 2: d/c
Page 3, Complex Number: 1: a+bi; 2: r∠Θ
Page 4, Statistical Frequency: 1: FreqOn; 2: FreqOff
Page 5, Contrast Setting
Operating structure has adopted the structure of the fx-50FH (a past model, it’s since been updated to the fx-50FHII).
Program Commands (P-CMD), available on both the fx-3650PII and fx-50FH series:
Page 1: ? (prompt), → (store), : (separator), ◢ (output/pause)
Page 2: ⇒ (jump/if-then-else), =, ≠
Page 3: >, <, ≥, ≤
Page 4: Goto, Lbl
Page 5: While, WhileEnd
Page 6: Next, Break
Page 7: For, To, Step
Page 8: Else, IfEnd
Page 9: If, Then
To exit program editing mode, press [ MODE ], [ MODE ], select 2 for RUN
When entering a new program, you are prompted to select the type of program at the start: COMP, CMPLX, SD, REG, or BASE.
Casio fx-3650 PII vs. Casio fx-50FH (II)
The main difference is that the fx-3650 PII has the numerical calculus functions integration and derivative, while the fx-50 FH has a library of scientific constants and 23 built in formulas. The fx-50FH has 680 bytes of programming memory.
The next post will have four programs that are done with both the fx-3650P and fx-3650P II to illustrate the programming differences.
Eddie
All original content copyright, © 2011-2026. Edward Shore. Unauthorized use and/or unauthorized distribution for commercial purposes without express and written permission from the author is strictly prohibited. This blog entry may be distributed for noncommercial purposes, provided that full credit is given to the author.
