PeST Questions & Answers
 
Q. Will PeST work with a modded ST running at 16Mhz?
A. Maybe.  There have been a few cases where PeST doesn't function correctly with a severely modded ST.  The reason for this is that when voltages and frequencies change it throws other parts of the system into confusion, you will no doubt be well aware of instabilities in setting up your system in the first place.  PeST is designed around a stock vanilla STFM, ie. a 100% standard machine.  What can be done to help those people with modded machines is to adjust the timing of the pulses which PeST sends out, by default these are 400uS (microseconds).  When a modded ST is getting confused by PeST the mouse pointer will repeatedly jump about and be uncontrollable, this can be rectified to some extent by changing the pulses to 600uS, 800uS etc.  The payoff in those cases is that the mouse isn't as responsive as it will be at 400uS.  A stock ST will function at 300uS although 400uS is the timing that everyone gets, specifically so that no one is ever dissapointed.  Those with modded systems get my full attention so there is some experience here already in working with systems that I've never seen or used.
 
Q. Does the PeST work with all PS2 Mice?
A. Yes.  All PS2 mice regardless of extra functions and scroll wheels etc. will work.  When any PS2 mouse is first powered it enters a default mode of XY 2 button operation, this is in keeping with the original PS2 standards.  Mice with extra functions and scroll wheels have to be sent a special command-string to tell them to enable their extra functions.
 
Q. I've heard that some PS2 mice have slightly different timings, is this a problem?
A. No.  The PeST waits for the high-low clock pulses from mouse, as opposed to checking the data line at a set interval.  The PeST will wait for upto 2 seconds.  This is different to the modded ST question up above.
 
Q. Will the PeST work through a KVM switch?
A. Yes, erm, and No.  Here's where it gets tricky and where we get technical.  The PeST will work with a manual switch KVM just fine, absolutely no problems at all.  With a digital KVM however, things get tricky.  The reason why PeST may have an issue with a digital KVM is that the manufacturers of these devices try to get clever, in that they will attempt to fool a normal PC into believing that the mouse is still there.  The PS2 industry standard defines that devices should only be connected with the power off.  Here's where we get technical.  PeST by it's design can error-trap and recover from a disconnected mouse.  What PeST does when no movement or button input has been received for 2 seconds, is to poll the mouse to see if it's there, it recognises a specific response that can only be achieved by the mouse being originally initialised by PeST.  This is why quickly disconnecting and reconnecting a mouse does not fool PeST into thinking everything is OK.  PeST knows when something has changed.  It's actually tempting to say that it will work with a digital KVM, as either way, PeST will simply reset itself and the mouse along with it.  The concern comes as some digital KVMs re-process the PS2 data packets, thus that PeST's operation with a digital KVM cannot be 100% guaranteed.  It's practically the same reason as why some PC's and mice / keyboards don't like digital KVMs and lock-up.  Now they never tell you that in the shop or on the box.
 
Q. Why do I need an extension cable for the PeST_029 when being used with an STFM?
A. The PeST_029 does not fit into the recess on the underside of the case on STFM style systems.  The cased PeST_029 was developed prior to the pcb PeST_030.  It's a matter of taste really although the PeST_030 exceeds requirements on the STFM, example , Atari were definitely making life difficult for it's customers on that day.  The PeST_029 is 100% ideally suited to the Mega STE / TT style of keyboards as the mouse port is so obvious and exposed, example.
 
Q. Do you use recycled packaging?
A. Yes, definitely!  Originally it seemed an idea to purchase new-recycled-boxes but they're just so ridiculously expensive, especially when you add on the P+P.  Plain foam lined boxes to ship hard disks are now being used when possible, these are sourced from a local computer store that previously had no other option but to break them down and dispose of them.
 
Q. Hi, Do you plan to market this device in the USA?  I'd love to get one for every machine I have but, the postage would kill me.  Thanks.
A. Hello, we've contacted Best Electronics in CA but that's looking unlikely at the moment as they want to pay less than what they're produced for.  I wonder if that's the reason why there are no Atari PS2 mouse interfaces for sale out there, because they're deemed not to be worth anything.  The postage on eBay is tracked Airsure with insurance so everything is as secure as it could be.  If you were looking for say 4 or 5 devices then I could easily do a fixed price and flat postage charge, drop me an email and we'll work something out.
 
Q. I trust you have tested your mouse interface thoroughly and it will not damage my TT030 in any way. Thanks, JH.
A. Hi J, rest assured that testing has been thorough.  We spent about 3 weeks testing the software side, the hardware side is practically foolproof as the aim was to minimise on components totally.  One thing we would recommend is that you plug and unplug the interface with the power switched off.  This is because the smoothing capacitor occasionally creates a sag in the +5v supply when it is introduced to the circuit.  We've noticed when reconnecting the original Atari ST mouse perhaps like 100+ times over the previous few months that it's not limited to PeST.  The recommendation as always when connecting anything is to switch the power off.  I'm sure this is a get-out clause that companies use to cut back on x number of hours in answering support questions.  You'll be fine.  At worst if you plug in / unplug the interface with the power on then the computer will just crash, the other 1% is unknown, hence the power-off advice.
 
Q. How long is the cable that comes out of the PeST?
A. The PS2 extension cable which comes out of the PeSTs sold here is 1metre (39") long, Chris's and 16/32's are 30cm (12")  long.  This is the same on both the encased 029 version and the PCB 030 version.
 
Q. What is your email address?
A. Ah, good point.  It is.., thinking of spam bots trawling the web here.  It's in the image at the bottom of this page.
 
Q. How do I buy the boxed PeST?
A. These are now made specifically to order.  Price is £35 inclusive of tracked P+P to anywhere in the world.  The price is in keeping with Chris's (my working partner) website; http://www.cps-electronics.co.uk/alison/web/index.htm
 
Q. Do you test these before shipping?
A. Yes.  Every single interface is tested prior to shipping and is also tested several times during assembly.  This involves checking that the mouse pointer moves as expected and that both buttons work correctly, setup mode is also entered and exited.  Generally the item is left plugged into an Atari ST overnight, so a soak-test of 12 hours.  The item is set to mode-3 (200% scaling) when shipped.
 
Q. What's this I hear about incompatabilities with the DEKA interface?
A. The DEKA interface is a replacement PS2 keyboard interface for the Atari ST.  It sports copies of the normal Atari mouse and joystick ports.  PeST will connect to the DEKA's implementation of the normal Atari mouse port.  The issue with PeST is that it is designed to work with the stock Atari keyboard, not through a third party system.  Due to PeST tracking much faster than the ST mouse, DEKA is not always able to keep up with the pulses.  We believe that DEKA was built around the stock Atari mouse and thus processes information to accomodate it, and it only  In saying that, DEKA is not standard Atari hardware.  PeST will however function but with limited scaling ability.  Please be aware.
 
Q. What happens if I pull on the cable?
A. If you pull on the cable the device comes out of the socket, naturally.  It is secured in such a fashion that it loops through holes and is held in place with a cable tie.  To physically break the cable from the device would require quite an amount of force.  If repeatedly connecting and disconnecting the device it would be suggested that you grasp the black sheath.
 
Q. Is it safe to use optical mice which draw 125mA, I'm using a TT.  Thanks, JH
A. We always look forward to your questions JH :-).  We would hazard a guess that 125mA is pushing the limits through an external MSTE/TT keyboard although in all honesty we're not totally sure.  Where the original STFM cases are concerned where the keyboard is internal this definitely isn't a problem as PeST was developed with one of these 125mA optical mice in question and has been powered for weeks on end.  System wise the TT keyboards are identical in operation to the internal keyboards; same chips, same specification etc. etc.  The only thing which would throw a spanner into the works would be the length of the coiled cable, being about 2 metres in length if uncoiled.  The PeST does have it's own smoothing capacitor to catch any irratic +5v supply, but at 2 metres that makes us wonder if further smoothing would be required.  Where the TT is concerned we're now tempted to suggest with the standard PeST (0.1uF smoothing cap) that a mouse that requires less than 100mA and one which doesn't use heavy sudden draining red leds to light the desk up be used.  If anyone is reading this with the intention of using PeST with a TT please let us know when purchasing.  The original ST mouse/joystick ports were used at times to supply floppy disk drives, 500mA+, so we know the power is there.  It wasn't highly recommended at the time however and was questioned, 1980's, and it's not necessarily recommended now.  100mA is not a huge drain, 500mA is.  And since our machines are now 15 years+ old the electrolytic capacitors in the power supplies could ideally be replaced to maintain optimum function, we've all seen how the screen can dim/flicker slightly when the floppy drive is being accessed, that's a struggling power supply  That 125mA figure will also be maximum power drain not constant.  It is an educated guess.  The final recommendation following this short debate is to minimise on mA usage with external keyboards where the +5v supply may be dirty.  The other recommendation is to replace the large electrolytic capacitors in your power supply, this is plain good practice.
 
Q. How many PeSTs are out there?
A. There are about 85+ PeSTs being regularly used now.  The 029 boxed versions only make up about 10 of these, with the remainder being the 030 sheathed PCB version.  Counties supplied to now include; Australia (about 5), Singapore (about 2), Italy (about 5), France (about 6), Spain (about 2), Germany (about 5), New Zealand (1), U.S.A. (about 15 or 20), Canada (about 5 or 10), UK (about 5 or 10), Netherlands (about 5), Russia (2).  That's about it really off the top of my head.  Touch wood, not one has been lost in the post yet despite going to all of these weird and wonderful places.  I'm totally paranoid about losing things in the post as it just winds me and the customer up, with the postal companies not caring one little bit.  Therefore every one sent has been via tracked post with basic insurance, I think the likelyhood of something going missing which is being 'watched' is far less likely.  The U.S.A. customers I'm most careful to keep happy as they quite rightly expect what they pay for, which I'm in total agreement with, and so therefore everyone gets U.S.A. style quality service.  The state of big company service now is absolutely diabolical and to inflicat that on people here would be totally not what I'm about.  Part of what you're investing in is for the entire sales process to be done properly, and for it to actually be done properly.  A little rant there me thinks, and the original question was only of how many PeSTs there were out there.