Accessing multiple printers

[NuY]

Hopefully, this is an easy one...

 

I have a 1020 plotter and a Canon BJ printer. Canon is connected via a Graphix AT (I think, not at home at the minute) parallel interface. If I chain the AT interface off the back of the 1020 and the 1020 is switched off, P: device times out when trying to print. Canon printer is online and receiving reset signals on power on. Is this a limitation of the 1020, in that even switched off, it won't pass anything to P: device?

 

Also, I recall reading that you can use P1:, P2: etc with multiple printers. This also doesn't work.

 

Canon works fine when it's chained off either my XF551 or 1050.

[Rybags]

That doesn't sound right, it's as if the +5 is getting through but the Command or Data line isn't.

 

How about try a disk drive or something else at the end of the chain. I suspect you might encounter the same thing.

 

Device ID shouldn't matter - when SIO devices are powered off they obviously don't take part other than passthru mode, and even powered up a SIO compliant device that's working properly doesn't have the means or reason to be able to inhibit communication to devices further down the chain, regardless of what their type/ID is.

 

You might also want to test the 1020's SIO jacks with a multimeter. Power it off, disconnect everything.

Each pin should have continuity to the corresponding pin on the other jack.

Edited October 1, 2010 by Rybags

[NuY]

That doesn't sound right, it's as if the +5 is getting through but the Command or Data line isn't.

 

How about try a disk drive or something else at the end of the chain. I suspect you might encounter the same thing.

 

Device ID shouldn't matter - when SIO devices are powered off they obviously don't take part other than passthru mode, and even powered up a SIO compliant device that's working properly doesn't have the means or reason to be able to inhibit communication to devices further down the chain, regardless of what their type/ID is.

 

You might also want to test the 1020's SIO jacks with a multimeter. Power it off, disconnect everything.

Each pin should have continuity to the corresponding pin on the other jack.

 

That's the thing - anything else that I chain off the 1020 works fine, 1020 off or on. SIO2SD, SIO2PC, even another drive all work fine. Odd.

[Rybags]

How about something other than the 1020 as the middle device?

 

Could be that the 1020 is barely letting the signal through and it's below the interface's threshold, or maybe the interface just needs a certain amount of current in it's signals to work properly.

 

Is the interface powered by the SIO plug or does it use an adaptor? Another factor might be that it's relying on the +5 V supplied by the computer. Some devices such as certain tape drives use that current to drive part of their circuitry.

[NuY]

It draws power from the SIO bus. Hanging it off anything else and it works fine - only off the 1020 it fails. My chain goes 1050 > XF > 1020 > whatever, the idea being that i can just use the 1020 to plug terminating stuff into until such time I get a Spider or similar.

 

I can't imagine what a printer interface would use in terms of SIO pins that anything else wouldn't though.

 

I'll try the 1020 as the first device in the chain later and see what happens. Thanks.

[Rybags]

There is the chance that the 1020 draws some power from the computer, depriving the interface of sufficient Amperage.

 

As ridiculous as it seems, the 410 and 1010 tape drives at least also do the same, even if powered off and not being used - I didn't know that at all until the recent "discovery" of the ability to generate a 6th "voice" by using that feature to create sound by toggling the drive control on/off.

 

As for what pins are used - as a minimum a semi-intelligent SIO device, ie anything other than a tape drive, uses Data In, Data Out, GND, Command. But daisy-chainable "middle" devices will pass through every pin whether it uses the signal or not.

Edited October 1, 2010 by Rybags

[+bob1200xl]

The printer interface gets it's power from the SIO, while the other devices you have plugged behind the 1020 do not. The 1020 is not passing +5v on to the chain...

 

Bob

 

 

 

It draws power from the SIO bus. Hanging it off anything else and it works fine - only off the 1020 it fails. My chain goes 1050 > XF > 1020 > whatever, the idea being that i can just use the 1020 to plug terminating stuff into until such time I get a Spider or similar.

 

I can't imagine what a printer interface would use in terms of SIO pins that anything else wouldn't though.

 

I'll try the 1020 as the first device in the chain later and see what happens. Thanks.

[Mathy]

Hello NuY

 

Also, I recall reading that you can use P1:, P2: etc with multiple printers. This also doesn't work.

P1: through I guess P8: should work. With the right printers. Meaning all (IIRC) 10x0 printers (1020, 1025, 1027, 1029) support this feature. But each type of printer had a specific number. So all 1025's could be accessed by either P: or (for instance) P6: And all 1027's would respond to P: and (for instance) P4:. I'm not sure which type of printer used what number, but you had to have different types (read: "Atari names") of printers. And the numbers where fixed, you couldn't change the numbers like you can on a disk drive.

 

sincerely

 

Mathy

[Mathy]

Hello NuY

 

Found the list. It was in an "Insight: Atari" article by Bill Wilkinson in the June 1986 issue of Computer. (One of the six issues I own and the second issue I looked at today)

 

850 -- P2:

1025 - P3:

1020 - P4:

1027 - P5:

1029 - P6:

 

sincerely

 

Mathy

[Rybags]

According to the 1020 schematics, it should passthru the +5V

 

It uses the +5V as input to a 75LS38, which appears to reset the printer if you power off the computer.

[NuY]

The printer interface gets it's power from the SIO, while the other devices you have plugged behind the 1020 do not. The 1020 is not passing +5v on to the chain...

 

Bob

That's what I thought it might be at first. I'm no electrical techie by any stretch of the imagination, but would not the SIO2SD be using the same +5v to power it? It also has no external power and draws power from the bus and works fine hanging off the 1020, and the Canon does do a reset (re-homing the carriage etc.) when the Atari is switched off/on...

Edited October 4, 2010 by NuY

[NuY]

Hello NuY

 

Found the list. It was in an "Insight: Atari" article by Bill Wilkinson in the June 1986 issue of Computer. (One of the six issues I own and the second issue I looked at today)

 

850 -- P2:

1025 - P3:

1020 - P4:

1027 - P5:

1029 - P6:

 

sincerely

 

Mathy

Thanks for that Mathy, I'll see if using other P: numbers will talk to either printer when both are on. I'll admit I only tried P1: and P2:.

[Rybags]

SIO2SD draws power from the Atari, yes.

 

Can't you just reorder the SIO chain in a fashion where the interface does work?

[NuY]

SIO2SD draws power from the Atari, yes.

 

Can't you just reorder the SIO chain in a fashion where the interface does work?

Without an SIO hub, the only option I have is unplugging whatever the last thing in the chain is and using it anyway. At the minute, chain goes Atari > 1050 > XF551 > 1020 > whatever is a terminating device, which at the minute is one of printer interface, SIO2PC, SIO2SD or XC12. I've still yet to try having the 1020 in the middle somewhere, is there anything inherently bad about having your 1020 first in the chain?

[Fox-1 / mnx]

whatever is a terminating device, which at the minute is one of printer interface, SIO2PC, SIO2SD or XC12.

Don't know what kind of SIO2PC device you're using but if it's a home brewed: build the interface in the middle of an existing SIO cable. Gently cut the outer side of the cable and pry out the wires you need to connect the SIO2PC. This way you can connect the thing in any situation.

 

Back in the day I even converted my (clone) APE-Face interface into such a configuration.

 

Or what I do most: build it inside the XL/XE or even inside a 1050/XF551/whatever.

 

 

is there anything inherently bad about having your 1020 first in the chain?

 

In theory, no, but my experience is that high-speed 1050 disk drives perform better when connected early in the chain when using a lot of daisy chained devices.

 

Once my sequence was like: 1050-Speedy -> 1050-Speedy-DS -> SIO2PC -> 1050-Happy -> XFD602 -> Turbo2000 -> XF551 -> 850 -> APE-Face -> 1020 -> 1010.

 

Later I got 2 Black Box's and devided the disk drives across 2 separate systems as more then 4 disk drives on the same system is just, well, not easy to handle :-) This also eliminated the use of an 850 and Ape-Face interface.