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Connor Angel
There is another thread on this subject that seemed to go pretty much nowhere here

There are instructions on creating an "almost" standard serial device out of a ps/2 cuecat with the title "Make your CueCat RS232 pod" inside the cuecat driver tar.gz, but unfortunatly it is not on the web outside that archive.

First off, I know very little about hardware, so don't take any of this seriously unless you do know the subject.

According to those instructions, you use a 74HCT04 Hex inverter, RS catalog #276-2804 to do the crude ps/2 to serial conversion, and then 3 AA batteries for the 4.5V the cuecat needs.

Now I have had problems with my main power socket on my Z, and one way I was able to test it was to plug a usb hub or car adaptor with an LED into the usb-client port on the zaurus and then plug a power source into the main power plug.

What I noticed is that the power flowed right into the car adaptor or usb hub and lit up the LED. My question is this. Is it possible that (assuming the Z's serial stuff handles the nonstandard cuecat modified for serial), would it be possible to use only that 74HCT04 Hex inverter, skip the batteries, and only use the cuecat while there is a battery pack plugged in to the main power port, letting the power from that flow through the usb/serial port into the cuecat?

Also, it would probably work great with this little adaptor -
Connor Angel
I should have been more clear. What I noticed about power in the proprietary usb/serial port is that it normally is not there at all when running off the battery, but once you plug in a battery pack or ac adaptor, it goes hot.

I took my usb sync cable and plugged that in to the zaurus, and then on the usb end plugged that into both (at different times) a usb hub with an LED, and a car charger with a usb port, and of course a LED. The usb ports and car chargers were not plugged in to anything but the zaurus. The power that was lighting up the LEDs on these devices seems to come from the external power source, because as soon as it is removed, those LEDs turn off. And since I was testing with a bad power jack, it usually flickered quite a bit (I did this test because the charge light is not as responsive).

That is why I think it might be possible to make a zaurus specific mod to the ps/2 cuecat that doesn't require batteries, although of course you would need a battery pack plugged in to the main power jack, but I already do that anyway.

Also, yeah I know the plans call for 3 AA batteries, but the ps/2 port is 4.5-5.5v, and those plans just go for the low end. The power from the zaurus should be just fine (I think), and I am more interested in not frying the zaurus than the cuecat.
Connor Angel
I don't expect many people to look in that tarball, so here is the document I was talking about. I didn't write any of this, just stripped the html and uploaded the pictures.

Make your CueCat RS232 pod

The purpose of this document is to describe how to make a small device that allows connecting a CueCat to a serial port.

NOTE : this serial pod only works because most modern serial ports are not too strict on the voltage levels representing a "0" or a "1" : in the definition of the RS232 standard, a "1" is coded with a voltage ranging from -3V to -12V, and a "0" is coded with a voltage ranging from +3V to +12V. Most modern serial ports will accept TTL levels as valid however, which means that they will accept 0V as a valid "1" (where they really shoudn't). Therefore, the pod's function is simply to invert the voltage coming from the CueCat's data line. If your serial port has stricter voltage level requirements, you'll have to replace the simple inverter with a specialized IC like the MAX232, to properly convert TTL to RS232.

The 2 advantages of this "incomplete" solution are :

It can't be cheaper

All the components are available at RadioShack, so you can buy them when you go pick up your CueCat :-)

Here is the schematic of the circuit :

Click to view attachment

Components you will need :
1 x 74HCT04 Hex inverter, RS catalog #276-2804 - $0.47
1 x Rectangular push ON/OFF switch, RS catalog #275-1565 - $2.19
1 x 1CB86 printed circuit board, RS catalog #276-0150 - $1.19
3 x AA single battery holder, RS catalog #270-0401 - $2.37
1 x Project box 4x2x1, RS catalog #270-1802 - $2.29
1 x Roll of double-sided foam tape, RS catalog #640-2343 - $1.99
1 x pack of 4 alcaline batteries, RS catalog #230-0873 - $3.19
1 x PS/2 extension cord - $1 at a computer hardware recycler
1 x DB9 <-> DB9 serial cord - $1 at a computer hardware recycler

Total : $15.69

Click to view attachment

Of course, you'll also need some tools, like a soldering iron, some solder, a phillips screwdriver, a drill, a knife ...

1 - Preparing the project box

The 3 battery holders together are just a little bit too wide for the width of the project box. So, you need to remove the plastic guides inside the box with a sharp knife or a cutter to gain 1 or 2 mmm :

Click to view attachment

2 - Installing the battery holders and the ON/OFF switch

Line up the 3 holders next to each other and stick 2 strips of double-sided foam tape under them. Then, stick the battery holders in the middle of the bottom of the project box (they will fit real tight but they will fit). Then, solder the wires serially to make a 4.5 volt source. Then, drill a hole on the side for the ON/OFF switch.

Click to view attachment

Insert the switch in the hole, put the washer on and screw everything tight.

Click to view attachment

Click to view attachment

3 - Making and installing the circuit board

Solder the 74HC04 on the circuit board and wire it up according to the schematic above. Cut the PS/2 extension cord in half and use the half with the female PS/2 plug. Cut the serial code in half and use the half with the female DB9 plug.

Once your board is ready, connect it to the power leads from the battery holders.

Click to view attachment

4 - Installing the circuit board and getting the cables out

Put 2 layers of double-sided foam tape on the solder side of the circuit board, then stick the board on the back of the project box's lid. On the side of the project box, dig a hole about 1cm deep and 4/5 mm wide. Tape the PS/2 cable and the serial cable together and slide them in the hold. You're about ready to close the box.

Click to view attachment

4 - The box finished with a CueCat connected and powered up smile.gif

Click to view attachment

NOTE : if someone is willing to build a pod, take more photos and document the process better, it'd be great, the above explanations are really lame (but it's late (early ?), so I have an excuse :-)

Click to view attachment
Connor Angel
Well nobody has shown interest yet, but i'm sure somebody will eventually wink.gif

I have decided to attempt this project and ordered the 5500/5600 docking connector, and a MAX232. I don't really understand why the hex convertor was used unless radio shack doesn't carry the MAX232 and it was a one day project. The MAX232 is only $0.50 more, I just ordered a couple off ebay. So now there is one less concern, it will be a valid serial device and less of a cheap hack.

My main concern is still power. Is that power coming out of the usb/serial docking jack usable in a device like this? Is it the same 5v that is going in the power jack? Will using it fry the zaurus or cause too much wear?

Even if using that power source is not an option, I think that it would be possible to just put a power jack somewhere on it (near where it connects to the zaurus) and then another cable to go into the zaurus, so it can get its power from the battery pack before it ever hits the zaurus. That way frying it wouldn't be an issue.

I plan on putting a button right on the cat's neck to turn it on for a scan, and then releasing it would cut the power. So even if the second powering route is taken and it is a battery hog, it won't hog it for long.

I am surprised that there has not been much talk on this board about this subject. Maybe everybody has moved on to usb capable zaurus models and are just using the usb cuecats.

It could end up being a nice clean looking hack. Without the need for its own batteries, it could have a black cord, a 5500/5600 connector (black too) spraypaint the cat black, put the MAX232 inside the cuecat (there is plenty of room), drill a couple small eyeholes and fill them with high density plastic plugs, put a red LED in there for the eyes to light up with the mouth, and suddenly it goes from a dorky looking ps/2 device into the coolest looking bar code reader ever seen cool.gif

Oh well. If a guru is reading this, please let me know what you think about the whole power coming out of the serial/usb docking connector issue. Is it the 5v I am expecting? Is it safe to use like this?
Well nobody has shown interest yet, but i'm sure somebody will eventual

um no offence but your post hasent exactlly been up for a long time and as far as i can tell very few people vist these fourmns on a day to day basis

that said, cool project, however i think that a better idea wauld be a camera and do all the hard work in software, it is more expensive but then you have a more flexible arangment

and yes i am aware at just how cheap the cuecats are, but i would rather hardware i could reuse or use at a longer range than the cuecat

all i have to do is connect an old webcam to my c3000, the joys of usb host
Connor Angel
QUOTE(Da_Blitz @ Apr 7 2006, 04:22 AM)
Well nobody has shown interest yet, but i'm sure somebody will eventual

um no offence but your post hasent exactlly been up for a long time and as far as i can tell very few people vist these fourmns on a day to day basis

Hence the winking smiley wink.gif I was just being sarcastic, but it can be hard to tell on the internet sometimes, even with those little guys.

that said, cool project, however i think that a better idea wauld be a camera and do all the hard work in software, it is more expensive but then you have a more flexible arangment

and yes i am aware at just how cheap the cuecats are, but i would rather hardware i could reuse or use at a longer range than the cuecat

all i have to do is connect an old webcam to my c3000, the joys of usb host

Kids these days. No appreciation for a good hack. You just plug in a usb device and... Yeah i'd probably do the same, but the zaurii with usb host are expensive, web cams too. I will probably do it that way once you move on to the newer models and I buy your old zaurus tongue.gif

P.S. Still wondering about the power that flows out of the serial/usb docking port when another power source is plugged in to the main power jack. I just checked it out with my multimeter and got 4.58V, so it looks good. I just worry that it was designed to be a power input and not a power output and it might fry the Z.
haha! excellent!
i always mis interpret that winking swily and have stoped using it, to me it looks as if the pearson is annoyed and hence my comment

want a good hack that does the same thing yet is still as flexible? laser pointer/LED and Light dependent resistor hooked up to the audio port smile.gif do all the decoding in software, the nice thing abut this is you can fit it all in a standard ball point pen

as a side note if you do this and instead use a magnetic card reader/field detector and a coil of wire you can scan and imitate those swipe cards with simple 'cat filename' cammands and redirections,

if you want you can even 'queue' the 'cat' commands eg cat filename1 ; cat filename2, sorry just had to say it.
Connor Angel
Ok. Well I have my max232 and zaurus i/o connector. I guess I will have to seal the hole in the i/o connector with hot glue because it is bigger than the cable. I will probably stick with the white cable because it has that plug thing that is lacking from the zaurus i/o connector. The on/off button (smallest radio shack had) should fit on the cat's back, without being all of the way on the big red C, leaving room for the max232.

I have the pinout for the i/o connector here,

The 74hc04 here,

And the max232, here

Serial, here

PS/2, here

So hopefully I can convert the original instructions to the zaurus and max232.

One question I have, other than is it safe to use the power input pins as power output with an external power source plugged in to the main jack, is about ground.

I am quite a hardware newbie, and had to look up what that arrow-ish symbol was and found that it meant ground. I see signal ground, power ground, and frame ground in the sharp i/o pinout. I am assuming that "frame ground" is what I should connect pin15 (GND) of the max232 to, and the wire that would have gone to pin3 of the ps/2 connector, had I not hacked it off with a knife and replaced it with the zaurus i/o connector. Is this correct?

Ground makes so little sense to me in a portable device like this. Yes, I know I should take a class on this stuff, and I probably will soon now that my interest for it is growing, but I want to build this now! biggrin.gif
Which ground you should use depends on what you are drawing power from, but in any case it is likely that all the gnd's are connected together

for power input as power output, try probing with a multimeter, if you see 5v's then you are ok i guess (ie no waranty implied or given by me smile.gif)

if you dont have a multimeter you can build one with a darlinton array (2 transistors) a 2 resistors and a LED, more af a continuity detector/voltage presscense indicator but it does the job, will post schematic if you need it but i would recomend a multimeter instead as they are handy
Connor Angel
Yup I have a multimeter and already tested the voltage, looks good. I just got the desoldering braid I needed yesterday, so today I will probably only have one soldering project - replacing my corroded power jack (see the 5x00 hardware forums in the off chance that you are interested).

I will be doing some more research tonight probably and then trying to do the cuecat thing tomorrow.

I figured the grounds would all be connected together. It seems odd that there would be more than one, but then again it also seems odd that the PS/2 port has 6 pins and only uses 4.
Thats normal for most plugs, they took an off the shelf plug and designed around it, thats why there are extra pins
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