Atari 8-bit newbie; trying to use SDrive-MAX

[echristopherson]

I recently bought a plain Atari 800. I just cobbled together an SDrive-MAX and got it working powered by the USB connector, but when I connect the SIO +5V line and remove the USB power supply it doesn't work right. It sort of turns on, but the screen doesn't always show the whole display (sometimes there are thin horizontal "scanlines" over parts of the screen)* and disk functionality seems to be missing. It doesn't finish drawing its UI until after the Atari has gone into BASIC or Memo Pad. Going by posts like this one here (http://atariage.com/forums/topic/212003-what-good-is-an-850/?do=findComment&comment=2748745), which say that the 850 allows the SDrive-MAX to boot up completely before the A800 is turned on due to the 850's dedicated power supply, I decided to reconnect the SIO +5V line and run it through the 850.

 

*(I may be misremembering whether the "scanline" appearance still persists in the newest SDrive-MAX I've built, when it's being powered only from the 800 with no intervening 850; it's possible only my earlier attempt which was really broken had that problem.)

 

However, the result seems to be mostly the same; the SDrive isn't powered on at all until I turn on the 800, and when it does sort of power up, the Atari doesn't seem to be able to boot from it. When I go this route, the screen starts out with the "scanlines" but those eventually get replaced by the actual contents of the screen; but by the time I have the normal UI screen displayed, the 800 is already in BASIC. There doesn't seem to be enough time for the SDrive to finish initializing before the Atari tries to boot.

 

Will BigBen's mod (http://atariage.com/forums/topic/286669-sdrive-max-and-atari-850/?do=findComment&comment=4189162) allow me to power the SDrive from the 850 and 800 alone?

 

More SDrive-MAX questions:

 

Is it dangerous to wire the SIO +5V line to the Arduino and have it also plugged into a USB power supply? I would assume so.

 

Is there an editable (e.g. STEP or IGES) file for Kbr's XL-style case? I've printed it from STL twice, using somewhat different 3D printer settings, but both times the bottom plate is too long to fit into the top without trimming; that and the pegs that go up through the Arduino are just barely tall enough to be flush with the board; I'd rather have them stick up a little bit above it.

 

Also, backing up a bit, I'd like to know what's the story with the Option, Select, Start, and System Reset keys as pertains to booting programs and restarting the computer. I've been looking around on Google and in these forums (and in the 800 Owner's Guide) and haven't found much. Specifically, I'm wondering if the advice to hold one or more of those keys while turning the computer on, or hold one or more of them while hitting System Reset, pertains to all 8-bits or just to XLs and XEs (for instance, I know that holding Option allows you to bypass BASIC on XLs and XEs, since their BASIC is built in and not on a cartridge). I've tried various combinations of them while trying to boot the SDrive-MAX and haven't found any of them to do anything noticeable.

 

Thanks.

[Gunstar]

The Atari doesn't supply enough amps on it's own when using some itself, through the +5V of the SIO to properly power the Arduino & touchscreen, you need a separate PSU, it mentions this in an updated version of the SDive-Max assembly/programming guide. It has to have it's own PSU, with enough amps (I think at least 1-1.5 amps, IIRC) to power it properly. Though this is usually more of an issue for XL/XE PSU with only 1-1.5 amps to begin with. Check out your 800's PSU amperage output on the PSU (unless of course you really mean you just got an 800XL), there are versions of 800's "universal" (also works with most 800 and XL peripherals) PSU that have more than 3 amp supplies. I have half a dozen of the 31VA (~3 amps) versions myself. Though since I already use more amps with all my upgrades, I still use a separate PSU for the SDive-Max, so it can be powered up fully before turning on the computer. Actually, IIRC, I didn't even bother hooking up the SIO +5V line to my SDrive-Max...maybe you are having an issue with it getting power from both ends...

 

As to the START/OPTION/SELECT keys, you hold START on a 400/800 to load from a tape, otherwise you do nothing since BASIC isn't built-in to the 400/800 and on cartridge. With the XL/XE line, you have to hold down the OPTION button when booting most software from disk(or virtual disk) or START&OPTION for tape to disable the built-in Basic. Reset is a soft-reset that many programs it just brings you back to the title screen, and anyway doesn't clear memory and whatnot like power-cycling does. There are Custom OS's that have reverse Basic so you don't have to hold down OPTION unless you want Basic on, and also combinations of Reset with another key to do a true cold-start reset without power-cycling, but not with stock OS's. I see you say the 800 is already in BASIC before the SDrive-Max boots...well, you shouldn't have BASIC cartridge inserted in most cases, when attempting to boot, so that may be a problem right there. But if it isn't due to BASIC being used, and you still have the same issue, you should be seeing a memo-pad screen...REMOVE THE BASIC CARTRIDGE!

Edited February 7, 2019 by Gunstar

[echristopherson]

Thanks, Gunstar; that clears many things up.

 

Actually, IIRC, I didn't even bother hooking up the SIO +5V line to my SDrive-Max...maybe you are having an issue with it getting power from both ends...

 

Well, luckily I haven't been foolish enough to have power connected in both places, yet. One of my questions was whether that was dangerous.

 

I see you say the 800 is already in BASIC before the SDrive-Max boots...well, you shouldn't have BASIC cartridge inserted in most cases, when attempting to boot, so that may be a problem right there. But if it isn't due to BASIC being used, and you still have the same issue, you should be seeing a memo-pad screen...REMOVE THE BASIC CARTRIDGE!

 

I'd like to be able to use BASIC and save and load programs. I understand that the only way to do that is to have the BASIC cartridge in and also boot from a DOS disk image; correct? I understand that for games and things the cartridge isn't needed and sometimes gets in the way (I have been able to run a few disk games with it in, but I believe Jumpman told me to take it out.)

 

Pity there isn't a built-in cold restart method. I assume people have hacked that functionality in the way they did for the C64. Personally I've been trying to do restarts by opening and closing the cartridge cover, thinking that saves a little strain on the power button; but for all I know it could put even worse strain on the cartridge cover sensor.

 

Oh, I forgot to mention the one issue I seem to have even when the SDrive-MAX is being powered properly: It doesn't boot from virtual drive "D0:" (as SDrive-MAX calls it). I understand that that drive is always supposed to be set to SDRIVE.ATR (i.e. you can't change it to another image). I do have that image on my SD card, and I've formatted the card and rewritten the image onto it multiple times, and verified that the image is an exact copy of the ones on the net, but when the SDrive-MAX is set to boot from D0: it just goes into BASIC or Memo Pad like nothing's there.

When I say "SDrive-MAX is set to boot from D0:", I mean that the D0: button near the bottom is selected (none of D1:-D4: is selected), and the option "Boot from D1:" in the config screen is not selected.

[Gunstar]

Oh, yeah, sorry about the Basic confusion. How you would go about that is turn on the computer to the Basic cursor prompt, then turn on the disk drive (SDrive-Max) and, IIRC, from Basic you either type "bye" "DOS" or "exit" (one or more of those) and then DOS should boot for you, then you just exit DOS and it will go back into Basic, and then you can save and load to a drive from Basic, IIRC. From that point saving and loading files is very similar to the way you do it on the C64 to start with( or you can go back and forth between DOS and BASIC and use DOS to save and load instead of Basic commands), without Basic it's autoload for other software just like a game console. Simple and newbie-user friendly.

 

But yes, normally, the computer should attempt to boot DOS if it is in D1:, with the Basic cartridge inserted, and then you would exit DOS or select start Basic from the DOS menu or whatever. So yeah, it is a bit strange if you get no boot with Basic, so you do need to have the SDrive-Max self-powered so it is ready before your computer is turned on and gets to the "ready" prompt. for it tow work that way.

 

It's not a sensor on the 800 cartridge door, it's a simple metal-to-metal contact. The door will wear out before the door power switch. I actually disabled mine so I can have the door open for taller cartridges and for reset switches on some flash cartridges so in combination with the reset button you do not need to power-cycle. And yes, the custom OS's I spoke of are hacked cold-start functionality like you say some have done with teh C64.

Edited February 7, 2019 by Gunstar

[_The Doctor__]

I have always bee a proponent of using a low voltage drop diode on the 5 volt in line of dual powered device to protect both machines, I even suggested it be installed in place of the 0 ohm resistor (also know as a jumper) on machines that need modding. I still think all Ataris should have a real 1.5 amp sustainable or greater power supply minimally ... The old xl stylized re-build-able power supplies do a good job, but the XE 1 amp and ingots or evil and should be used for cords and parts or demolition fun...

 

If a device is 'dual' power capable I'd probably just use external power and not connect the Atari power line to the device at all if possible and no noise, looping, or level differentials are at play.

Edited February 7, 2019 by _The Doctor__

[Gavin1968]

You can not power it by the USB! That will destroy something! It is best to not power at all via SIO but used a 12VDC external power supply for the Arduino. The ones I build I put a switch in it so people can power either via SIO or external (NOT USB) power but not both and fry something.

[talanthalus]

Power:

• I'm using the external supply provided by Gavin with my SDrive-Max. My 800XL will not power it on its own, as there is simply not enough power going to it off the SIO to work.
• My switch is a little loose, so it accidentally got moved to the SIO power side while plugged in. The result was power going back to the 800XL, but nothing will work when you turn on the computer. I will be eliminating the switching option for future use or set the switch in, so it has to be changed by using the stylus or something to move it.

Boot:

• Set Boot D1: in the CFG screen and save. Make sure you have an ATR that is bootable in the D1: slot. Make sure your physical drive, if attached, is set to D2 or higher.
• Usually I select the D1 entry, so it is highlighted, and it will boot.

 

It is a great device once you get the hang of it. Don't use SpartaDOS, apparently, because it is a bit flaky, though two of my bootable ATRs are SpartaDOS formats. I'm still learning the rest by trial and error.

[Gunstar]

You can not power it by the USB! That will destroy something! It is best to not power at all via SIO but used a 12VDC external power supply for the Arduino. The ones I build I put a switch in it so people can power either via SIO or external (NOT USB) power but not both and fry something.

Who mentioned powering by USB? If I said USB anywhere it was a mistake. I was always referring either to 5V power from the SIO or power via the barrel plug input on the Arduino intended for power, not the USB you use to program it with. BUT, even through the Arduino's power input, it's still 5V isn't it? just more amperage required than can be supplied through the SIO. If I mentioned USB, I meant the PSU itself being USB; goes from USB output to the Arduino's barrel power input, NOT the USB input on the Arduino. But, can't you program the Ardiuno with only 5V power coming through it's USB port connected to the PC? Or does it still need to have it's own PSU while programming?

 

I recently finished assembling mine, but I've been having issues attempting to program the ATmega328, but I have not plugged a PSU into the Arduino, just attempting to program it with only the USB cord between the PC and Arduino. That's how it looked like it was programmed in the youtube video I watched on how to program it. I don't recall the Arduino being powered through it's PSU input...and that is enough for both the Arduino and the shield to both turn on, but maybe they aren't getting enough power that way to program them? I bought a 5V 2.5 Amp USB PSU for it, but have not tried to power it with that 5V PSU yet...does it really need to be powered by 12V PSU? If that is the case, then why would anyone have thought it could be powered via the SIO at any amperage since it is only a 5V line?

Edited February 9, 2019 by Gunstar

[Gavin1968]

Who mentioned powering by USB? If I said USB anywhere it was a mistake. I was always referring either to 5V power from the SIO or power via the barrel plug input on the Arduino intended for power, not the USB you use to program it with. BUT, even through the Arduino's power input, it's still 5V isn't it? just more amperage required than can be supplied through the SIO. If I mentioned USB, I meant the PSU itself being USB; goes from USB output to the Arduino's barrel power input, NOT the USB input on the Arduino. But, can't you program the Ardiuno with only 5V power coming through it's USB port connected to the PC? Or does it still need to have it's own PSU while programming?

 

I recently finished assembling mine, but I've been having issues attempting to program the ATmega328, but I have not plugged a PSU into the Arduino, just attempting to program it with only the USB cord between the PC and Arduino. I bought a 5V 2.5 Amp USB PSU for it, but have not tried to power it with that 5V PSU yet...does it really need to be powered by 12V PSU?

The original post who I was responding to. Not you As far as 12VDC goes, that is what I use for the ones I build and sell. Also, you can power via USB for flashing and setting it up, just not for use while attached to the 8bit machine.

 

I have built almost 100 of these drives now, I am pretty fluent in building them

Edited February 8, 2019 by Gavin1968

[Gunstar]

The original post who I was responding to. Not you As far as 12VDC goes, that is what I use for the ones I build and sell. Also, you can power via USB for flashing and setting it up, just not for use while attached to the 8bit machine.

 

I have built almost 100 of these drives now, I am pretty fluent in building them

That is fine. I edited above, but you replied before I got it up, the SDrive-max really requires 12V PSU? If so, then why would anyone have ever thought it could be powered via 5V SIO at any amperage? I thought it needed to be powered with external power from a 5V PSU, but needs around 1-1.5 amps which the SIO can't supply to it and the computer at the same time...

 

EDIT: oh, wait, you mean you use 12V PSU's but they don't have to be 12V? They can be 5V? I just want to make sure I give it enough volts and amps to power it once I figure out why I can't get it to program (I suspect the Arduino I got has a bad ATMEGA328 on it...every time I try to program it, I get a response that "programmer not responding" then 10 attempts for it to sync without success and then "failed to program" or whatever.

Edited February 9, 2019 by Gunstar

[Magic Knight]

I use this device only via SIO from the Atari. Absolutely no issues in running files, touch screen or copying to the flash card any other way.

 

Wouldn't dream of powering up independently of SIO. Perfect device... Thumbs up to the people who devised this!

[Gunstar]

It depends on what Atari computer you have and it's PSU having enough amps for the computer and Arduino. So you must have a PSU that puts out enough amperage to do it that way. Many do not. As far as I am aware, the 600/800XL & XE PSU's don't have enough amperage on their original PSU's. The 400/800/1200 with 31VA "univerals" PSU's do have enough amperage to power the Arduino via SIO. But there are also some of the "universal" PSU's that are less than 31VA (U.S.-and also PAL land "universal" PSU's with, IIRC, 27-28VA), but I don't recall how many amps they have.

 

But even though my Atari's do have enough PSU amperage to power the Arduino, I use that extra amperage for my current and future upgrades and am the exact opposite, and wouldn't have it any other way than using the Arduino with it's own PSU, and save my computer's amps for powering internal upgrades. The only peripheral that takes power from my Atari via SIO is my Supra Microprint interface.

Edited February 9, 2019 by Gunstar

[Magic Knight]

I probably get away with it, as I only ever have one SIO device plugged in normally. Although I use SIOUSB and a 1050 occasionally for copying, the SDmax is always plugged straight in with no other SIO devices attached.

 

My unit is pal with 1.5A classic brick. But I think as it only uses around 0.8A (IIRC) there's still some wiggle room for drawing more current despite having U1MB installed.

[SS]

I am using one of Lotharek's new A8 power supplies and do not have any issues powering the SDrive-MAX via the SIO port. Lotherek's PS outputs 5V and 3A; I don't think that I would want to try to run my U1MB machine and SIO powered peripherals with a OEM 1.5A power supply.

[+DrVenkman]

I am using one of Lotharek's new A8 power supplies and do not have any issues powering the SDrive-MAX via the SIO port. Lotherek's PS outputs 5V and 3A; I don't think that I would want to try to run my U1MB machine and SIO powered peripherals with a OEM 1.5A power supply.

 

Works just fine on my U1MB 1200XL and a stock 9VAC power supply.

 

I have since modified my unit to use a standard Arduino UNO PSU, however, since I was testing with my 800 for awhile; the 800 boot-up time is so fast that it's already booted (to Memo Pad) before the Arduino has loaded the SDrive-MAX firmware, read the card and is ready to go. With a U1MB-equipped machine, that doesn't matter - once the Arduino has booted, you can select your image files for the drive slots, then cold-boot the machine from the U1MB BIOS. So SIO power worked great in that application, but with a 400 or 800 it doesn't.

Edited February 9, 2019 by DrVenkman

[Brentarian]

So SIO power worked great in that application, but with a 400 or 800 it doesn't.

Since the Sdrive-Max can run on 12V, I wonder if SIO pin12 on the 400/800 is sufficient enough to power it.

[Gunstar]

The same issues that DrVenkman had would still be there, whether the power on the SIO is 5 or 12V. It's not a power issue, it's a boot issue. But other than that, it all depends on the amperage on the 12V line, I would guess the amps are the same, since the power all comes from the same PSU, unless the 400/800 boosts amperage on 12V with a built in amplifier circuit for it, or amps are less over 12V for some reason. I haven't studied the 400/800 power distribution. But assuming the 12V line gets at least as many amps as the 5V, which I see no reason it wouldn't, yes, it should work in my estimation.

 

There are two versions of (NTSC) PSU's for the 400/800 and peripherals. One that has 9V, ~3 amp (Input 120V/60Hz/50 watt)and works with almost every peripheral for the 800 and XL lines, and one that is 9V, 1.7 amp(Input 120V/60Hz/18.5 watt) and will not work with the 1050 or 810 drives, but is suitable for most other 800/XL line peripherals. If the second version is used for the 800, I am not sure it would have enough amps left over to power the SDrive-MAX right, because I would hazard a guess that the 800's consume more amperage than XL/XE's.

 

I'll have to look into it, now that I have an 800, even though I have no plans of using an SDrive-MAX with it. Just so I know for sure how the power is distributed for other reasons.

Edited February 9, 2019 by Gunstar

[Gunstar]

I just skimmed the power usage of the 400/800 in the field service manual, and I can't find mention of amperage, only volts, so I have to assume the amperage is the same across the board (figuratively, literally and actually ), and depends solely on the PSU's amperage output.

Edited February 10, 2019 by Gunstar

[Gunstar]

A correction, I decided to take a second and actually do the math, the NTSC/60Hz land 31VA universal PSU's are ~3.44 amps, not ~3. I knew they were more than 3 amps from checking a long time ago, I just forgot that it was closer to 3.5 amps than 3. The PAL/50Hz land universal PSU's are 28VA or 3 amps.

Edited February 10, 2019 by Gunstar

[_The Doctor__]

what is the output after regulation? on each output of the ps board in the 800?

[Gunstar]

If you are referring to output amperage, as I said, I found nothing on that in the FSG (of course I skimmed, and might have missed it), it only talked about voltages like I said, so I am assuming amperage output is the same as whatever amperage the PSU that is being used outputs to the 800, even after regulation, regardless if 5 or 12V on each output. Until someone who knows different says so. Otherwise I guess the only way to find out is to put a multimeter to the ps board outputs.

Edited February 10, 2019 by Gunstar

[+DrVenkman]

Just so everyone is 100% clear, amperage is not constant - the rating is simply the maximum output the PSU can maintain reliably (theoretically anyway). I=V/R after all. Voltage is contant (theoretically).. Overall circuit resistance as seen by the PSU will vary with the machine's operation, internal configuration, loads drawn through the SIO or joystick ports, etc. That is what determines how much amperage is being drawn through the PSU moment to moment ...

[Gavin1968]

All,

Here are the specs for the Arduino,

https://playground.arduino.cc/Learning/WhatAdapter

As you can see this device likes 9 to 12V DC, 250mA or more, 2.1mm plug, center pin positive.

Yes, it will work on the SIO power, BUT, since SIO is not powered with the computer off, you will not be able to boot to the SDrive-MAX if it does not have external power, at least not on the A800.

That is why when I sell mine I sell them with a 12VDC power supply. Yes, it is overkill, but they are cheap so why not?

The Arduino runs on very low amperage so that may be why 5VDC from SIO is enough to run it but it is being under powered.

 

Thanks,

Gavin

[Gunstar]

All,

Here are the specs for the Arduino,

https://playground.arduino.cc/Learning/WhatAdapter

As you can see this device likes 9 to 12V DC, 250mA or more, 2.1mm plug, center pin positive.

Yes, it will work on the SIO power, BUT, since SIO is not powered with the computer off, you will not be able to boot to the SDrive-MAX if it does not have external power, at least not on the A800.

That is why when I sell mine I sell them with a 12VDC power supply. Yes, it is overkill, but they are cheap so why not?

The Arduino runs on very low amperage so that may be why 5VDC from SIO is enough to run it but it is being under powered.

 

Thanks,

Gavin

Good to know. So I am not going to use the 5V 2 amp USB PSU I got for it then. I'd read somewhere when starting this project that the SDrive-Max required about 800mA and somewhere else I read 500mA and yet another place 1 amp for both the Arduino and LED Shield combined, so then just to be clear, that 250mA is what the Arduino alone requires, but with the LED Shield that requirement would increase? Maybe around the 800mA - 1 amp mark?

 

I have some 9 and 12V DC PSU laying around, I'll have to see what amperage they supply, I may not need to buy another PSU

Edited February 10, 2019 by Gunstar

[Gavin1968]

The ones I supply are 12VDC 1A and they run perfectly. That is what I have used in all of the ones I have built and no one has ever reported any problems or issues using then. I go with what works