I got my first
$1 scientific calculator from a local Dollar Tree Store in 2009. A
2011 closed HP Forum thread discusses it, and it is very impressive for the price. I thought these notes I compiled about it might be useful to others.
Code:
* Look carefully for the dark red key legends, used only in special
calculator modes: A B C D E F for HEX mode entry. n <mean> <s> DATA
for STAT mode entry (DATA) and results.
* Complex example 1+j2 * 4+j8 = -12+j16: CPLX 1 a 2 b X 4 a 8 b = (-12)
b (16). Only + - * / are available, not exp, log, trig, sqrt, etc.
* Polar <-> Rectangular example: 3 a 4 b ->r<theta> (5) b (53.1 deg)
->xy (3) b (4).
* Statistics example: STAT 3 DATA 2 DATA 1 DATA n (3) <avg> (2) s (1)
<sum_x> (6) <sum_x^2> (14) <sigma> 0.816. Clear last entry by CD.
Clear all by STAT (exit the mode).
* Working Register (x <-> y) example: 3 / 6 <up/down arrow =
2nd ( keys> = (2, 6/3 instead of 3/6).
* Working Register ("constants") example: 2 * = (4) = (8) = (16) =
(32) / 2 = (16) = (8) = (4) ...
* HEX mode appears to be 40 bit 2's comp ("0 - 1 =" shows FFFFFFFFFF)
but it isn't 40 bits. HEX Mode arithmetic is limited to +/- 1e10-1
(10 decimal digits) -- Do this: 9999999999 (10 9s) HEX (= 2540bE3FF)
+/- (= FdAbF41C01), good. "- 1 =" shows "E" error. Guess: HEX is
converted to DEC, 10-digit integer math done, then back to HEX.
log2(2e10) = 34.2 bits. So the HEX is limited to 34-bit 2s
complement operations, ~= +/- 2^33 ~= +/- 8.6e9.
* BIN mode seems to be limited to 10-bit 2s complement (-512 to +511
decimal). BIN 111111111 (9 1s) can +/- OK, but adding 1 to it results
in Error (overflow). Similarly, 1000000000 (-512 decimal) - 1 =
Error.
* Base Conversion Ranges
Binary 1000000000 to 0111111111 (10-bit 2s comp, -512 to 511)
Octal 4000000000 to 3777777777 (10-digit 2s comp octal)
Decimal -9999999999 to 9999999999 (+/- 10 digits)
Hex FdAbF41C01 to 02540bE3ff (same as the Decimal range)
* Display mode: TAB 0-9 (# of decimal places), TAB . (default general
display), F<->E (floating point vs exponential toggle, only applies
to the range 1e-9 to 1e10-1).
* An extra digit is kept in addition to the 10 displayed. 1 + 1e-10 =
(1) - 1 = (1e-10). Doing the same with 1e-11 doesn't work.
* Application: 1 + 1e-10 = x^2 x^2 x^2... (41 times) ~= 3.2e95 and
is still in range. This is x^(2^41). 1 + 1e-10 = y^x (2 y^x 41)
= (the same result).