Strange FSBUS Behaviour

[Guest GeorgeDorkofikis]

Good morning everybody.After a loooong period of research, desgin etc, I started the actual manufacturing process of my FSBUS system.This will consist of a full 737NG MCP, full radio stack, EFIS and maybe later a basic overhead.This post has two problems. One concerning flashing the PICs and the other concerning the software.Until now I had successfully flashed 2Key, 1Led, 6Displays (1board).But I came across to a very strange problem. As you know the display board consists of 6 display PICs with their respective attachements (crystal, capacitors etc).My first display board (and all I mention above) flashed without a problem with the first try.But on the second display board I had a very strange behaviour!Four (4) of the six (6) PICs on the board flashed with the first try without a problem. But the other 2 refused to flash. I got the infamous 'Read after write' error! I measured the board and I noticed I had a small hairwidth shortcircuit. As soon as I cleared it, the respective PIC flashed ok. The remaining 2 PICs still refused to flash.When I measured them I had 8V on pin 12. Looking and measuring again I did not find any shortcircuits or broken routes.But when I physically moved the PIC to another position (that had flashed ok), it was flashed without problems!!!Any ideas please? I know it's a long shot, but did anyone else had this strange behaviour? All look fine from the hardware point of view, although I am still looking and maybe I missed something.Now, on the software thing. When running the FSKEY test whatever I have connected to SubId 3 also closes SubId 7. To make it clear.I have connected a simple push button to a row (doesn't matter which, it occures in ALL rows/banks) and at subid 3 (pins 5+6, Bit 3).When pushing on the button I get a closed contact on Bit 3 + on bit 7!! But I have nothing connected to Bit 7!I'm using the latest v2.0.8. Anyone else seeing this? I checked the key board and there are no short-circuits whatsoever!On the same subject, I noticed a very strange behaviour of the SPEED handling! While ALL other variables are working great, IAS it's very jerky and very unstable. What happens is that when I turn right or left to increase or decreasde the speed changes by 2 (that's another bug, see below), then goes back 1, back 2 , forward 1 and so on. If I continue turning I get strange speeds all over until it settles down to a value. While looking at the FS at the same time I noticed that the speed was indeed changed ok but then reverted back to the oscillation/jerkyness that I was seeing in my FSBUS display. So I assume the problem is with the FSBUS software.I also checked with all prior versions (2.0.2 - 2.0.8) and it happens with all.I control the speed via a rotary/Redec combination. At first I though it may be the rotary that is faulty, but when I assigned that specific rotary to Heading or Course they worked great. This occures only with IAS.Another problem still not solved is that all the changes using rotaries via redec increase/decrease by a factor of 2. If the step is set to 1, the changes are made by 2, if set to 100, the changes are made by 200 etc. It's not a redec problem because this did not occure on ver 2.0.2. It's a bug of v2.0.4 afterwards. I already emailed Dirk about this but haven't got a reply yet. Probably, he's still on vacation :-) or simply very busy.Sorry for the long post. Hopefully the problems each of us have and manages to solve will help others solve them too.Regards,George DorkofikisAthens, Greece

[oal331 0]

Hi,about h/w problem, i have also the same problems. I had to increase the input power from 9v to ~15v and i have no errors in PIC flashing.I'm afraid that FsBus ComIII needs input 9V not stabilized, so when switching to a cheap pack i have to 9v it gives me ~15V. And when switching it to 7volts it gives me 10,5v. So if the input power is 9v stabilized, maybe is not enough for flashing.I don't have any problems with 15v input for flashing and return back to 9-10 for normal operation.About s/w, i think the best one to reply is Dirk, which has too much things to do but he is absent many weeks now from here (this forum)!!! Sorry i don't know if in any other English forum he is replying, i prefer English :-)I hope that he is fine and working on a new version !!!!regardsEddie ArmaosAthens-Greece

[Guest cesurkanat]

Hi George,I also got the same problems too.1-Flashing: I solved that famous "read after write error" by switching to Windovs XP software. Altough Display kart denied flashing the farter 2 PICs I chosed to restart PC, and used realitvitely short flashing cable. Yes it worked.2-IAS got same problem too. When you are turning rotary (I use knitter) faster, as your current displayed value in MCP reached around 200 it suddenly drops to zero. the faster you turn the more frequently gaps occur. Treatment: I prefeer adjusting the speed slowly and patiently.3- When I turn two rotaries at the same time fs bus router progrem stop responding and you should close and restart it.4-on final aproach when you push APP in mcp you will see that the aircraft only captures localizer not glideslope.5-Heading values displayed in MCP is switches to true heading, not the value you have set.6-In previous version of router (2.02) on start up, touching only just one switch in MCP was enough to awakening all leds and display, but in newer version you have to touch everyone both pushbuton and rotaries. As you said you are going to build full scale MCP, EFIS, and radios how do you think to solve other problems like wiring Disengage bar,how to make A/T ARM switch travels of when disengaged from thrust levers etc.Hope to discuss theese later.Regards.Remzi OzturkLTBA /TURKEY

[Guest GeorgeDorkofikis]

Hi Remzi,Had seen your MCP photos on your earlier post and loved it! Very well done! I may be distrurbing you some time later about the backlighting... :-)1. Flashing. I already use WinXP. Rebooting did help and that's how I managed to flash the 4 out of the 6 PICs in my 2nd display board. But the 2 refused to flash until I moved them, flashed them, them moved them back!Edit: Finally found the problem... Although I measured the boards there was 'cold' solder in 2 of the pins of the jumpers!2. For me it doesn't return to zero. It just flickers back and forth (actually to the oposite direction that I'm turning).3. Never tried it. Why would you need to do that?4. Now that you mention it... I did an auto approach and I noticed it followed just the LOC, but then again I WAS a biiit high on the glide, so maybe that's the reason. I will check again.5. Hmmm... Heading functioned ok during the tests I've made so far.6. Can't comment :-)I haven't thought about those things yet... Probably a big toggle switch will do the trick. As for the A/T arm, I don't know. Maybe it's possible via the D/O board (via a relay) and the use of an electromechanic switch. But those are expensive and big!George DorkofikisAthens, Greece

[tigert 0]

As for the power supply, I run mine on 12V from a PC AT power supply. You just need a heatsink for the voltage regulator (the heavy-duty three-legged component with a hole on its metal head)Tuomas

[Guest GeorgeDorkofikis]

The 7805 is certified up to 16-18V input voltage if I recall correctly.So it's not a big problem. The heatsink is a must even at 9V if you have more than 1 board connected.I don't know how much current the FSBUS boards draw when all connected (I will measure it sometime) but I hope it's less than the max 1A that the 7805 is rated!Eddie, check and double check your COM board. I get clean 13.5V after the 680Ohm resistor with the same regulated PSU you use.George DorkofikisAthens, Greece

[oal331 0]

Hi,>Eddie, check and double check your COM board. I get clean>13.5V after the 680Ohm resistor with the same regulated PSU>you use.>>George Dorkofikis>Athens, Greece>I think i need the "FsBus/doctor" to visit the sick-circuit !!So, i can arrange a very good pizza-dinner tonight in my cockpit captain, so just ask for it and the cabin crew will be there :-)hehehe!!!Eddie ArmaosAthens-Greece

[Guest rahulsh]

George,Funny that I had the exact same issues with my display cards as well, with the exact same number of problems. As is turned out, there were two shorts and one cold solder!!!And I'm building a 737NG with the works as well - jut have to figure out how the hell to wire up the overhead with the PMDG 737TNG!!!On the auto throttle cutoff from the throttle levers, one idea I had was to use a Miniature Circuit Breaker (MCB), modified to fit the A/T Arm switch. There is a test pushbutton available, that simply demagnetises the switch and flips it off. Connecting this pushbutton to the Throttle switches would do the trick... The same thing can be applied for the A/P cutoff on the older 737s. The trick is to modify the MCB to resemble the A/T Arm switch...