August 2016 63
signal, swapped LSB and MSB, and
many other tweaks.
When that didn’t work, I opened
up the device and soldered leads
directly to the TX and GND pins at
the IR transmitter. I then connected
the leads to my signal analyzer and
also my oscilloscope. I verified the
baud rate and also noticed that the
voltage levels were TTL, not RS-232. I
borrowed a TTL to USB adapter, but
this did not work either.
I came to terms with the fact
that the data is compressed and/
or encrypted. So, I searched far
and wide for some software for this
device and I found it ... well at least
a similar device. I installed and ran it
in a variety of configurations and still
cannot get receive data that makes
any sense. I have done enough testing
and playing around with this product
where I can almost write a book, but
I still have no success in transferring
the data to another similar device or
to a computer. I have searched for this
device on Google, eBay, Amazon, etc.,
and they are extinct. I’ve purchased
a slightly newer generation of this
product, but I do not believe that
they are compatible. I have called
the manufacturer, but they no longer
support the device. So, I am at a total
dead end. I have read your magazine
for many years and thought that this
would be the perfect venue for a
Nuts & Volts case study/project for
DIYers and the like. I would greatly
appreciate any advice that you
might have in doing what I originally
expected to be a relatively simple
problem to solve.
#1 Have you opened the device
and identified its processor? The
data through the IR ports may be
compressed, but the data sent to the
display isn’t compressed, and maybe
easier to capture as LCD digits and
segments. Then, you can convert that
back to ASCII and send it to a new
The next problem is how to
attach to the LCD digit and segment
signals without doing any damage
to the original device. The scan
frequency is necessary to sync the
signals at the right moment when
being read. The processor ID will give
you the correct signal pins and help
reading through a second device.
The last solution is to read the
data on the LCD one-by-one and
type the information manually to the
newer computer. It may be the only
Raymond J Ramirez
#2 Wow, lots of work so far! Could
you stick a chip clip on the memory
chip and monitor it while trying a
transfer (to force it to dump the DB)?
Maybe it isn’t encrypted until the IR
transfer; that is, unencrypted coming
out of the memory chip ... obviously,
assuming there is one.
#3 “Google is your friend,” as I
keep telling my girlfriend.
A 10 minute search on Google
revealed a couple of interesting
Apparently, RadioShack had, at
one point, sold a computer interface
for this device, though given the
manual on their website, I’m guessing
it was 20 to 30 years ago.
Also, I saw references in other
places that it’s possible to get the
Rolodex to transmit a single record.
If you really want to decode it,
what I would suggest is to set up to
record the signature of the IR signal
(Digital Storage Oscilloscope?), and
have it send a known [short] entry.
(Maybe do so a few times in case it’s
using something that changes each
transmission.) Then change one letter
in the known entry, and send it again.
With some patience, you should be
able to break the code.
(I really doubt that they got very
heroic about security on this gadget,
especially as it’s quite old.)
Of course, if you really want a
challenge, you _could_ decode the
LCD code. (Remember that LCDs
require a balanced signal, so go both
positive and negative to the actual
#4 I’m not familiar with this device,
but I did a lot of similar stuff when
this was probably built.
In the early days, the only real
serial standard was RS-232 which
used ±15V. These ‘new pretenders’
could not supply this, so many used
0-5V only. This just fell within the spec
so that a standard port could talk to it
There’s also the pain of getting
handshaking right on adopters, etc.
You don’t have a real port to deal
with, having tapped into the IR part,
but it could help explain some of the
Although there’s no RS-232
port, data coming via IR may not be
reliable without software handshaking
(e.g., XON/XOFF with ASCII), but
ASCII is not the only kid on the block.
It could be EBSDIC or more likely as
memory was always at a premium,
encoded with reduced bits (think
teletype close with shift-in and shift-out).
If you’re determined to do it in
hardware, bare the above in mind,
and that most interfaces only like
Or, try to tap the LCD feed? But,
as the display is still just working, why
not just re-key all the data — surely
that would be quicker?
What a challenge! Good Luck!
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