Does anyone know the difference between model # 82240A and model # 82240B? What were some of the updates to version B? I recently obtained an HP 82240A which seems to work without any problems with my HP48 calculators. It apparently also works with the HP95LX AC adaptor!

Hi,

as far as I know, the only difference (besides a green led vs a red one) is that the character subset in the B version is a bit bigger, but it doesn't really make a difference in final output and you can choose an option at least in the 48G series to work with one or the other.

Hi,

The 82240B has an extended caracter set ECMA 96. It was introduced for the HP-48 series.

http://www.hpmuseum.org/cgi-sys/cgiwrap/hpmuseum/archv009.cgi?read=23762

Virgilio

Note that although the ASCII characters match in the two character
sets, the non-ASCII characters (128-255 decimal) don't. The 48 and
49 series include the OLDPRT command to remap, where possible, the
new calculators' character set to the 82240A's character set, and
otherwise the remapping is to character 127. All characters
actually used in built-in command names are remapped correctly.
The remapping string is stored in the reserved variable PRTPAR,
and you can change it if you prefer. If you run OLDPRT and then
print to an 82240B, the remapping will be incorrect; in this case
just purge PRTPAR (the default PRTPAR will be created it as
needed), or change the remapping string to "", the empty string.

Of course a pair of escape sequences for switching character sets
were added; these are ignored by the 82240A. The 82240B uses the Roman 8 character set by default,
so older calculators work just fine with it. Any printing (except
by the CR command, and perhaps the PRLCD command) from the 48
series starts out with the escape sequence to switch to the new
character set, so it works fine with them too (as long as the
remapping string is empty). If you print to it with a 48 series,
and then, without doing a reset or power OFF/ON, print to it from
a calculator using the Roman 8 set, it will use the wrong
character set.

Besides adding the modified ECMA-94 (ISO-8859) Latin 1 character
set, some of the characters were modified to avoid having
characters with descenders meet the top of characters in the next
row.

Also added is a "low-power" mode. When running on battery only, it
switches to this mode after about ten minutes of inactivity. It
doesn't switch to this mode when external power is supplied.

A visible red "power on" LED is added, but note that this is
turned off in the "low-power" mode. Unless you want to retain mode
settings or data still in the input buffer, I advise switching the
printer off when you're through using it; even "low-power" mode
must use "some" power.

The dot on the power switch seems to be red on the 82240B, and
orange or green on the 82240A.

The "ID letter" at the end of the self-test is G on the 82240Bs
that I've seen, and D or not present on the 82240As.

Of course there could be internal changes to either the 82240A or
82240B.

Scans of the Owner's Manuals for both models are included in the
latest MoHPC CD ROM set / DVD, and additional information is
available
here.

Regards,
James

Edited: 3 June 2006, 5:02 a.m. after one or more responses were posted

Thank you all for the great information.

I have yet one more question. I my manual, it states that I should not use the printer with only the AC adapator. That is, I should have batteries installed even if I plan to use the AC adaptor. However, the manual never explains why, or what happens if I do.

Does anyone know why I should not use the printer with only the AC adaptor and no batteries?

I've used my printers without batteries (external power only) with no apparent problems, but I generally prefer to follow the instructions in the owner's manuals and always have the battery installed for printing.

Note that you don't have to use a "genuine HP" adapter, as long as your external power source meets the voltage and current requirements. The input power can be either polarity of DC, or it can be AC. I surmise that there's a bridge ("full-wave") rectifier in the circuit for external power.

Regards,
James

Edited: 2 June 2006, 11:11 p.m.

PS:

Except within column graphics escape sequences, unused ASCII
control codes and escape sequences are ignored by the printers.
These are (in decimal notatation) control codes <0>-<3>, <5>-<9>,
<11>-<26>, and <28>-<31>, and escape sequences <27><167>-<27><249>
in the 82240A, or <27><167>-<27><247> in the 82240B.

ASCII control code <127> and non-ECMA-94 codes <128>-<159> are
printable characters on these printers.

Character <160> (ECMA-94 non-breaking space character) prints as a
space in the ECMA-94 character set. In the 48 series, it's displayed as a
space, and the compiler treats it as a separator. In the 49
series (using the built-in fonts), it's displayed as the Euro
symbol, and it's not a separator. The printers don't have a
built-in Euro symbol, but I suppose that a column graphics
escape sequence could be used for that.

Regards,
James

Edited: 3 June 2006, 12:33 a.m. after one or more responses were posted

Quote:

---

Does anyone know why I should not use the printer with only the AC adaptor and no batteries?

---

The AC adapter does not supply enough current by itself during heavy printing (when printing lots of black). This is why the manual states that the AC adapter should not be used without batteries installed.

PPS:

I suppose that the escape sequence <27><0> is also "unused", or maybe the printers treat it as a "zero-length" column graphics escape sequence.

Regards,
James

At least that's what the owner's manuals state.

Experimentally, my printers have a problem printing solid black column graphics when powered by only an HP F1011A adapter (12VDC 0.75A), although they work fine when powered by only an HP 82241A adaper (9VAC 13.5VA MAX).

I suppose that what it comes down to is that the printers can draw power from the battery if the external power source isn't able to supply enough. Whether the battery is really needed seems to depend on which external power source you use.

Regards,
James

Quote:

---

At least that's what the owner's manuals state.

Experimentally, my printers have a problem printing solid black column graphics when powered by only an HP F1011A adapter (12VDC 0.75A), although they work fine when powered by only an HP 82241A adaper (9VAC 13.5VA MAX).

I suppose that what it comes down to is that the printers can draw power from the battery if the external power source isn't able to supply enough. Whether the battery is really needed seems to depend on which external power source you use.

Regards,
James

---

I see. I also happen to own the HP F1011A adaptor (for my HP 200LX), and was wondering if it was possible to use it since the voltage rating for the printer (according to the manuals) states 9V-12V. However, I think I will stick to the HP 82241A adaptor since it is actually mentioned in the manual.

The box that the F1011A comes in says that it powers "HP Palmtop
PCs" and "HP Infrared Printers". Also see the "All Parts" listing
for the 82240A in the HP
PartSurfer. The F1011A should be just fine, although the
82241A can supply more power.

I find the F1011A easier to carry with me. On the other hand, the
F1011A seems to run a lot warmer; whether it's wasting more power
as heat or it's warmer because it lacks the ventilation slots
found on the 82241A, I don't know.

Of course any external power adapter that supplies 9-12 V AC or DC
and at least 500 mA should also work. Don't pay too much for a
"genuine HP" adapter on eBay, unless you want it as a "collector's
item". That said, I expect that, with patience, you can probably
get one at a price comparable to a new non-HP adapter.

On reflection, the problem with running on an AC adapter only may
be that although the adapter may, on average, be able to supply
more power than the internal battery, even after rectifying and
filtering by the printer's circuits, under load the voltage from
the AC adapter would have some ripple. Perhaps under a heavy load,
the voltage between pulses can drop too low, and this is where
power from the battery is needed.

Regards,
James

The B model has better power management and battery life. If I remember right it basically goes to sleep when idle for a while.