Atari 400 SIO peripherals not working

[+DrVenkman]

9 minutes ago, a8isa1 said:

I'm not so sure about all SDrive-MAXes, especially homebrewed ones.

Most of the ones sold by people commercially in recent years have an external switch to select power sources. Home-built ones may or may not. That’s up to the user. In my experience, I found SIO-power for my SDrive-Max to be extremely flakey for most of my machines, and the boot time for the Arduino was too slow to make it reliable when SIO powered, so I disconnected the +5V lead and went with external power full time. 

[The V-Man]

On 1/8/2022 at 6:50 AM, DrVenkman said:

Swap the POKEY from your questionable Incognito 800 into your known-working 48K 800 and then test the FujiNet again in the 48K machine. If it works, the issue is the serial I/O function of that POKEY.

Well, I swapped a good pokey in and it exhibits the same behavior.   I have an Atari 810, so I think I'm going to connect that to it and see what happens.  It seems that I'm down to a bad trace or maybe the PIA chip even though it did not appear that way when testing the joystick ports.  I've tested the ports below with the following resistance like @ApM did on the 400. There is power running to fujiNet as I can "change" drives with the A button and the blue light blinks without an external power supply. 

 

SIO 1 - POKEY 26 (Clock in / BCLK) -- 100 Ohms

SIO 2 - POKEY 27 (Clock out / ACLK) -- 100 Ohms

SIO 3 - POKEY 24 (Data in) -- 100 Ohms

SIO 5 - POKEY 28 (Data Out) -- 100 Ohms

SIO 7 - PIA 19 (Command) -- 100 Ohms

SIO 8 - PIA 39 (Motor Control) -- Infinity

SIO 9 - PIA 40 (Proceed) -- 100 Ohms

SIO 13 - PIA 18 (Interrupt)  -- 100 Ohms

[+DrVenkman]

2 hours ago, The V-Man said:

t seems that I'm down to a bad trace or maybe the PIA chip even though it did not appear that way when testing the joystick ports.

PIA is only involved in serial I/O for control of the cassette MTR line. For actual reads and writes, POKEY is doing all the work. 

[The V-Man]

well, looks like it does not recognize the 810 drive as well.  I even created a colleen mode with everything disabled and 48k.  Whether I have anything connected to the SIO or not, when I turn it on I get a quick buzz sound, like a fast SIO load sound for a half a second then it goes to the memo pad. 

[TGB1718]

On 1/12/2022 at 4:33 PM, DrVenkman said:

so I disconnected the +5V lead and went with external power full time. 

I did exactly the same on the 2 I've built, not worth taking chances of blowing something

[The V-Man]

Get ready for this!!! 

 

I tried a working Pokey, PIA, and even a new motherboard without Incognito and nothing worked.  However, when I took the power supply to my working Atari 800, it no longer was able to access the SIO.  Put the old power supply back, and everything worked again.  And this is a NEW power supply! It supplies power, but for some reason its blocking SIO access??? 

[_The Doctor__]

what power supplies are you using? provides ratings and numbers... what your saying sounds like a wrong supply...

 

[The V-Man]

3 hours ago, _The Doctor__ said:

what power supplies are you using? provides ratings and numbers... what your saying sounds like a wrong supply...

 

I'm sorry bad choice of words.  The AC to DC power board inside the Atari 800 is what was the issue.  All power supplies I have work with the good power board.

[_The Doctor__]

then it's not so strange. you either have a failed component(s) or bad connection on the non working board, we've seen bad connectors, pins, headers, and failed caps transistors, diodes... well you get the idea...