Compucorp 344 Statistician

Datasheet legend
Ab/c: Fractions calculation
AC: Alternating current
BaseN: Number base calculations
Card: Magnetic card storage
Cmem: Continuous memory
Cond: Conditional execution
Const: Scientific constants
Cplx: Complex number arithmetic
DC: Direct current
Eqlib: Equation library
Exp: Exponential/logarithmic functions
Fin: Financial functions
Grph: Graphing capability
Hyp: Hyperbolic functions
Ind: Indirect addressing
Intg: Numerical integration
Jump: Unconditional jump (GOTO)
Lbl: Program labels
LCD: Liquid Crystal Display
LED: Light-Emitting Diode
Li-ion: Lithium-ion rechargeable battery
Lreg: Linear regression (2-variable statistics)
mA: Milliamperes of current
Mtrx: Matrix support
NiCd: Nickel-Cadmium rechargeable battery
NiMH: Nickel-metal-hydrite rechargeable battery
Prnt: Printer
RTC: Real-time clock
Sdev: Standard deviation (1-variable statistics)
Solv: Equation solver
Subr: Subroutine call capability
Symb: Symbolic computing
Tape: Magnetic tape storage
Trig: Trigonometric functions
Units: Unit conversions
VAC: Volts AC
VDC: Volts DC
Years of production: 1972-1975 Display type: Numeric display  
New price: USD 795.00   Display color: Orange  
    Display technology: Plasma fluorescent display 
Size: 9"×5½"×3" Display size: 10+2 digits
Weight: 4 lbs    
    Entry method: Algebraic 
Batteries: 4×"D" alkaline Advanced functions: Exp Lreg 
External power: 7VDC 1.3A   Memory functions: +/-/×/÷/^ 
I/O:      
    Programming model: Keystroke entry 
Precision: 13 digits Program functions:  
Memories: 10 numbers Program display:  
Program memory: 160 program steps Program editing:  
Chipset:   Forensic result:  

cc344.jpg (52942 bytes)The Compucorp 344 Statistician was the high-end business-oriented member of Compucorp's fabulous handheld calculator product line. (The statistical line had no equivalent to the top-of-the-line scientific model, the 326.) Like its scientific counterpart, the Compucorp 324G, the 344 had room for 2 programs, maximum 80 steps each. It also had a full complement of one and two-variable statistical functions.

I received this 344, my first statistical Compucorp machine, a few weeks ago; it was in a non-working condition. Taking it apart and cleaning some of the contacts helped, but only to a certain extent; now I got some garbage digits and characters on the display, but nothing more. However, this was enough to verify that the display itself was functional (although there was some bleeding around the edges of heavily used display segments, indicating that this machine was used a lot) so I promptly proceeded to swap the display module with that of my 322G, which (I thought) was working fine except for a dead display.

Well, I was wrong. My 322G still doesn't work, but my 344 mysteriously came to life after display surgery! Which means a lot of good news and some bad news. Good news because I have a working 344. Good news because the display module from my 322G, which I thought was dead, is also working, giving me reason to hope that I'll be able to restore that machine one day as well. Bad news because my theory about the cause of its malfunction was proven wrong. So much for theories in the face of ugly facts; but who cares about a broken theory when the facts aren't ugly?

The programming model of the Compucorp 344 is essentially identical to that of the Compucorp 324G, the only difference being the different set of special functions (trigonometric and scientific functions on the 324G, statistical functions on the 344.) Like the 324G, the 344 also sports the unusual 2ND FUNCkey that is applied after a dual-function button has been pressed, and merely swaps the contents of the display with a temporary register that contains the result of the secondary function.

The Gamma function program example I wrote for the 324G can be used without alteration on the 344. Here it is again, reproduced for completeness. To use this program, you must also populate registers 4-9 with constant values:

M4=√2π
M5=68.82784822
M6=755.9596084
M7=4151.488796
M8=11399.36541
M9=12520.43913


01	STn
02	2
03	STn
04	3
05	1
06	+
07	RCLn
08	2
09	=
10	STn
11	×
12	3
13	=
14	STn
15	×
16	3
17	=
18	STn
19	×
20	3
21	=
22	STn
23	×
24	3
25	=
26	STn
27	×
28	3
29	+
30	.
31	5
32	ax
33	(
34	-
35	2ND
36	5
37	)
38	÷
39	2ND
40	ex
41	×
42	(
43	RCLn
44	4
45	×
46	RCLn
47	2
48	+
49	RCLn
50	5
51	×
52	RCLn
53	2
54	+
55	RCLn
56	6
57	×
58	RCLn
59	2
60	+
61	RCLn
62	7
63	×
64	RCLn
65	2
66	+
67	RCLn
68	8
69	×
70	RCLn
71	2
72	+
73	RCLn
74	9
75	)
76	÷
77	RCLn
78	3
79	=
80	STOP