Incognito - Now's your chance!

[adam242]

I have two Lotharek Incognitos for sale in the Marketplace forum. Much faster shipping for US buyers.

[TGB1718]

Finally bit the bullet and ordered one, can't wait to fit it.

 

Also an SIO Splitter and cable.

[Jeffrey Worley]

3 minutes ago, TGB1718 said:

Finally bit the bullet and ordered one, can't wait to fit it.

 

Also an SIO Splitter and cable.

You are going to be beside yourself with glee.  If you need any help, message me and I'll make myself available by phone or chat or whatever way makes sense.

 

Personally, I didn't want to do the button mod the way the videos do.  If you don't, I have a simple way that requires no mods to the case yet still allows ATR swap capability.  I built five of these machines.

 

best,

 

Jeff

[TGB1718]

Many thanks for your kind offer, I may be in touch in a few weeks when it arrives

[Jeffrey Worley]

On 2/19/2020 at 3:39 PM, TGB1718 said:

Many thanks for your kind offer, I may be in touch in a few weeks when it arrives

You don't have to wait on the ATR swap button to build the thing.  Go ahead and build without the button.  My version is a little PCB you hide under the Ram-slot cover, on the left-rear.  You access the swap button with a naked q-tip rod or a straightened paper clip.  It also has an LED on it, which is bent to be visible through the air vents.  I sent some photos up on the Atari Facebook page some time ago, but I'd be happy to take some more and give you all you need to get your's up and running.  I have the PCB's, leds, switches, colored switch caps....  Enough to make oh, maybe 25 or more.  I only needed 5, but you know how online buying is.  1 is as cheap as 50.  Mine just plugs into the Incognito and three wires lead under the card cage lid three inches to where you locate the board.

 

It might have been here I posted those shots.  Take a peek around this topic a couple of months ago.

 

best,

 

Jeff

Edited February 21, 2020 by Jeffrey Worley
Completeness

[+slx]

If you go through the thread there‘s a post on how to use a capacitive switch that allows disc swapping by just touching the power light. 

[Jeffrey Worley]

4 hours ago, slx said:

If you go through the thread there‘s a post on how to use a capacitive switch that allows disc swapping by just touching the power light. 

I toyed with the idea awhile before someone actually did it.  I don't have those switches and do have eensy weensie Arduino project Switches.

 

Running wires between the two boards, from the main to the power board, bothers me.  It would make the machine harder to service.  I sold four of them and wanted them to serve for another 40 years.  This way, the only service needed to fix/replace a switch, would be to remove the card-cage lid.

 

Best,

 

Jeff

Edited February 21, 2020 by Jeffrey Worley

[+DrVenkman]

25 minutes ago, Jeffrey Worley said:

Running wires between the two boards, from the main to the power board, bothers me.  It would make the machine harder to service.

Not if you know how to make Dupont connectors.  

 

 

[flashjazzcat]

1 minute ago, DrVenkman said:

Not if you know how to make Dupont connectors.

And that's even shown in the video...

[Jeffrey Worley]

Just now, DrVenkman said:

Not if you know how to make Dupont connectors.  

 

 

I use them a fair bit, but not having a crimper for them, or the volume to justify it, I use pre-made ones from Amazon.  Mine plugs into the Incognito's header with dupont connectors, but the leads are only 3 or 4 inches long.  This one, pictured, is the first one I made, so it is not very pretty, and has been removed more than once. The copper tape connects the ground wire to the shield.  In a first-installation, the tape is nice and smooth and pretty.

 

 

 

 

[TGB1718]

Fantasic, it's turned up in just 6 days from Poland, well packed, now I have to plan the time to do this.

 

I love the litle sweet Lotharek puts in the box ? even though I can eat it.

[TGB1718]

Here's a thing, I've been toying with many ideas for the ATR swap button as I didn't want to do the mods as

shown on @flashjazzcat excellent videos, I was looking at either a photo sensor through the top grill or a touch

sense pad.

 

Then I had one of those ? moments, I mentioned earlier that you could possibly use the RF channel select switch

but would mean flicking it on and off.

 

I had a look at the circuit diagram and it was obvious that the switch had to be a 'break' before 'make' otherwise

you could short 5V to 0V.

 

So a minor mod, cut the track on the 5V side from the switch, connect 0V to that pad, so both pads have 0V on them,

now when you slide the switch, momentarily you remove the 0V from the centre contact and then it re-connects,

this happens whichever way you slide the switch, so connecting the centre pad to the ATR swap connection on the

Incognito board and you have your swap switch with only the smallest changes.

 

It may require a pullup to 5V on the centre pad, won't know for sure until I try this, but it looks like it might work.

 

If by chance it won't work if the swap input is held low most of the time, then it would need something like a small board with a 

7404 invertor connected between the centre pad and to one input of the 7404 and the output to the swap.

 

Even so it would be a tiny board with a single chip on it, not complex and easy to fit.

 

What do you think ???

 

P.S. I have checked the switch with a meter and it does 'break' before 'make'

Edited February 25, 2020 by TGB1718
Forgot to say

[Jeffrey Worley]

What I did was connect the led anode to pin 3 of the header, led ground to pin 2, and connected one side of an spst switch to pin 1 of the header.  The second leg of the SPST switch I taped to the 10lb aluminum shield with copper foil tape.  This was after trying to share the center pin for ground with the led and it not working.

 

best,

 

jeff

Edited February 25, 2020 by Jeffrey Worley

[TGB1718]

Just thought I would update this, although I haven't had the time to install the Incognito, I wanted to sort out

the ATR swap switch first, I followed up on the idea of using the Channel Select switch as I will never use RF

(many years ago I had already made use of the switch to do a "cold" start without turning the 800 off, so the

tracks were already cut.

 

Heres what I did, first a small circuit that is necessary as the switch output is LOW, goes momentarly HIGH and 

then LOW again, ATR swap is a LOW pulse.

This circuit provides a normally HIGH output, but when triggered, produces an approx. 220ms LOW pulse.

It does this whichever way you push the switch, so slide one way and you get a pulse, or slide the other way

and still get a pulse.

 

I temporarily connected the circuit to my 800, powered on and flicked the switch back and forth, see waveforms,

each LOW pulse is when the switch is moved one way or the other.

 

Using this method gets around having to do the power indicator MOD or finding some other way which may include

drilling a hole for a switch. This uses an existing redudant switch, so no external mods needed.

 

The circuit board I've used wil be cut down to make it smaller.

 

The only thing I've found is that the switch may be oxydized in one direction due to lack of use, so a good clean

of the contacts should sort that, then I'll be good to go.

 

 

[+DrVenkman]

Clever use of a 555 in what's essentially the mono-stable mode. Seems kind of complicated though - remember, you're effectively just replacing the functionality of a single momentary switch, which is already de-bounced by the Incognito. It seems like if you want to use a 555 to generate a fixed-pulse signal, you should be able to use the output directly. 

 

But hey, I love the 555. I built this yesterday just to play with it.

 

(This is a variable speed Larson scanner made using a 555 and a CD4017 decade counter - useless but fun).

[TGB1718]

The 555 output goes high when triggered, so needs to be inverted, it's triggered by a low, so again the input from the 

switch also needs inverting.

 

btw, I've hit a problem, started on the wiring, did the links on the MB and change the 2 resistors, then started to wire

the 6 pin socket, connected red and white as in @flashjazzcat shows in his video, then went to put the next 2 wires

on RD4 and 5 and I noticed I don't have a Blue wire, so checked the plug against the descriptions and it looks like

all the wires on my socket are not just different, they look like the ones that are correct and not in the right pins.

 

Anyone else got one like this, I don't even know which end is pin 1 to try work it out.

[flashjazzcat]

16 minutes ago, TGB1718 said:

Anyone else got one like this, I don't even know which end is pin 1 to try work it out.

Ignore the wire colours and go by the pin numbers. Pin 1 is at the end of the 6-way header closest to the edge of the PCB.

[TGB1718]

46 minutes ago, flashjazzcat said:

Ignore the wire colours and go by the pin numbers. Pin 1 is at the end of the 6-way header closest to the edge of the PCB.

Thanks, just found a photo on this thread from @DrVenkman , his has the same wire colours/sequence as mine, so from that

 

Pin 1 Green

Pin 2 Orange

Pin 2 Yellow

Pin 4 White

Pin 5 Red

Pin 6 Black

 

Thanks for the advice/help 

 

 

Now where did I put my desoldering tool .......

 

Resoldered and corrected wires, quick power-on and I see the Incognito BIOS screen.

 

Now just the LED's, ATR switch, a bit of filing and think it will be done,  a job for tomorrow...

 

thanks again.

Edited March 2, 2020 by TGB1718
Extra info

[+DrVenkman]

20 hours ago, TGB1718 said:

The 555 output goes high when triggered, so needs to be inverted, it's triggered by a low, so again the input from the 

switch also needs inverting.

Yes it does, but when the output (pin 3) goes high, the discharge (pin 7) goes low. If you set your resistors and discharge cap right, you'll get your inverted pulse just fine with no need for external transistors. 

Edited March 3, 2020 by DrVenkman
typo

[TGB1718]

Slowly worked my way through the rest of the installation, powering up and checking as I go, evrything seemed ok.

 

Finally put it all back together, powered up, again all looked good until I tried to change the settings.

 

Sod's law applies here, a set of keys, <RETURN> being one not working, I've checked the matrix and

its all the keys on row 3 of the matrix i.e. UIOP-=<RETURN>

 

So its take appart and (fingers crossed) check and clean the contacts.

[TGB1718]

Sort of lucky and unlucky, did some continuety checks and found an intermittent connection from the RETURN Key to

pin 3 on the ribbon, so I didn't blow anything doing the upgrade.

 

As I moved the ribbon during the checks the contact came and went, tried a resolder of the joint on the keyboard, still the same.

 

I removed the keyboard from the housing and could see where the ribbon cable entered the keyboard PCB, it looked like the

copper wires had corroded on the exposed wire where it entered the PCB and to my horror, just the act of removing the keyboard

had caused over half of the wires to seperate from the PCB, so at least I know whats caused this, I have now removed the cable

cleared the holes and started a repair stripping the wire ends, tinning in preparation to refitting.

 

That'll teach me never to leave this baby in a garage again as it had been for many years, obviously the damp has caused this.

[TGB1718]

Ok, fixed the keyboard and it seems to be working fine now, tried the ATR swap that I made and that works fine too,

only thing is the HDD LED does not flash when accessing the HD, I used a Blue LED for the power light and a RED one 

for HDD light, the reason for that choice is I read somewhere in this thread that some LED's don't seem to work, so I

checked the voltage across both LED's before fitting, the BLUE was about 2.8V, not knowing the output voltage of the

HDD LED driver (may be 3.3V) I thought a drop of 2.8V maye not allow it to light.

The Red LED was 1.8V and I checked it lit on 3.3V and 5V and it was fine, so chose this as the HDD LED.

 

Is there a particular type of LED I sould be using ?

 

I wired as per the instruction on Lotherek's site:-

P6 pinout goes as follows:

• pin #1 - HDD LED anode
• pin #2 - HDD LED cathode
• pin #3 - switch

Edited March 4, 2020 by TGB1718

[TGB1718]

Might seem a bit of work to get the HDD LED flashing, but I have found times when the 800 is doing stuff and there is no

indication that it's not actually frozen, so having the LED flash as intended gives some reasurance.

 

So here's my fix, it's not for everyone, but it's cheap and only takes about an hour to make and fit.

 

The circuit uses an NE555 timer IC, although it's not using the Timer Function, it's making use of the comparitor

circuit and trigger, essentially it will have a LOW output if the input is HIGH and will flip HIGH if a LOW is presented

to the input. 

From my measurements of the LED driver output on the Incognito, Pin 1 is normally HIGH (~3.6V) and goes LOW

when it's supposed to light the diode.

 

No further mod's needed to the 800, just a few extra wires to power the circuit and connections to the LED and attach

Pin1 of Incognito to the input to this circuit.

 

If you do this mod, make sure the wires you use are long enough to reach the opposite side of the 800, there is virtually

no room, even for the wires between the circuit bouards of the 800 and the plastic case. I ran the wires behind the joystick

ports where there is no chance of crushing or catching on anything.

 

Finally I just used a tie wrap to attach the small circuit board to the plastic base, I didn't want to drill any holes and this is

very secure anf there's nothing to touch/short to on that side of the case.

 

I just tied back the spare LED wire from Pin 2 on the Incognito, maybe if I have to take it appart some time I will remove

the wire from the connector.

 

And finally a small video of the flashing LED (maybe I should have rduced the brightness of the blue LED, but hey it works and you can see it.

[+DrVenkman]

I can’t see your video (Safari on iPad OS here), but I like your concept. I’ve got a bunch of 555’s around here, and a chunk of perfboard too. I might duplicate your circuit some day.

[Faicuai]

44 minutes ago, TGB1718 said:

Might seem a bit of work to get the HDD LED flashing, but I have found times when the 800 is doing stuff and there is no

indication that it's not actually frozen, so having the LED flash as intended gives some reasurance.

 

So here's my fix, it's not for everyone, but it's cheap and only takes about an hour to make and fit.

 

The circuit uses an NE555 timer IC, although it's not using the Timer Function, it's making use of the comparitor

circuit and trigger, essentially it will have a LOW output if the input is HIGH and will flip HIGH if a LOW is presented

to the input. 

From my measurements of the LED driver output on the Incognito, Pin 1 is normally HIGH (~3.6V) and goes LOW

when it's supposed to light the diode.

 

No further mod's needed to the 800, just a few extra wires to power the circuit and connections to the LED and attach

Pin1 of Incognito to the input to this circuit.

 

If you do this mod, make sure the wires you use are long enough to reach the opposite side of the 800, there is virtually

no room, even for the wires between the circuit bouards of the 800 and the plastic case. I ran the wires behind the joystick

ports where there is no chance of crushing or catching on anything.

 

Finally I just used a tie wrap to attach the small circuit board to the plastic base, I didn't want to drill any holes and this is

very secure anf there's nothing to touch/short to on that side of the case.

 

I just tied back the spare LED wire from Pin 2 on the Incognito, maybe if I have to take it appart some time I will remove

the wire from the connector.

 

And finally a small video of the flashing LED (maybe I should have rduced the brightness of the blue LED, but hey it works and you can see it.

That's the GTIA speaker port / slot... Where is it?