SystemEmbedded.eu

Introduction
Inspiration for this mode was nightly discussion with some friends and their request to make device which will be capable to connect ant EPSON/IBM printer to Atari. We had MicroPrint on the market in the past but nowadays it’s rather not possible to find it and use with any printer with Centronics. In case I developed VIAtronics – it’s combination of VIAtari (presented year ago) and Centronics (actually only cable from it). Idea is very simple: connect VIAtronics to CART/ECI with cable LPT (DB25) -Centronics (C36) and any printer which can emulated EPSON or IBM codes. Project was made as Free Hardware under Creative Commons BY-NC-SA 4.0.

This is the first project created as part of the activities of PTODT (Polskie Towarzystwo Ochrony Dziedzictwa Technicznego, which means the Polish Society for the Protection of Technical Heritage), founded for the protection of technical heritage, especially in the field of informatics and computers.

Edit 1.
There is available VIAtronics CART version witch may be use with Atari 600XL/800XL and Atari 65XE without ECI port (maybe with 800 but I haven't it for test).

Edit 2.
I developed additional version of VIAtronics with vertical orientation and fully pass thru.

Edit 3.
Waiting for new part of VIA chips I found Intel 8255 peripheral port chips... ready to use as cheaper alternative for VIA6522. VIAtronics v.2.2 (codename INTari) was designed.


Hardware
PCB based on standard CART/ECI slot contains VIA6522 two 8-bits parallel ports with control signals. Additional IC 74HCT138 is use as address decoder. All required by printer signals are connected to DB25 female port. On the PCB you may find selector for device address which can be selected from $D100-$D1E0 or $D500-$D5E0 with $20 step ( for INTari version it's $D180 to $D1F0 or $D580 to $D5F0 with $10 step ). Additional four pin header are connected to PA/PB/CA/CB signals and might be use for other task depend of your idea If you are using cartridge e.g. Koala Illustrator or some text editor, you may use it together with VIAtronics but you need to check addresses used by cartridge to avoid conflict with VIAtronics. There is a few differences between VIAtronics CART/ECI, VIAtronics CART and VIAtronics 2.2 (INTari) which were described below.

Software
The old software that allows printing on 8bit Atari computers does not support the VIAtronics interface for apparent reasons: the interface did not exist during their creation. But Anyone who knows the basics of programming on 8bit Atari can write such a driver for his printer. It is enough to see the printer control codes, usually found in the printer manual. The most common control codes standards used by old printer manufacturers are Epson and IBM. The program above uses Epson or IBM codes.

If the user does not want to code the printing program himself, he can use the only program at the moment that supports printing with the use of VIAtronics – “Drukarz” (means “Typesetter” in English). The freeware program was written and is still in active development by AtariFan. It allows you to print graphics via SIO
(on Atari 1029 and printers connected via the classic Centronics interface) and VIAtronics. The program enables basic operations on the image before printing (mirror image vertically and horizontally, moving up/down, left/right, negative). It can be downloaded from: http://atari8.eu or from the utilities archive on http://atarionline.pl as well as other tools such as “VIAtronics Tester” or “HATABS”.



Design - VIAtronics 1.0 CART/ECI version
On the begging I planned make the CART/ECI version only for 65/130XE but when under tests - first page was printed, I decided to make the interface more available for other users... but now let's talk about the first version...
The idea is that you may use interface not only for printing... you may use this device for everything you want to connect to parallel two ports! e.g. display, COVOX, speech synthesizer... anyway, when I received PCBs I found description's mistake on the board:
Don't worry, it's exist only on my developing board and has no influence to working device. Attached schematic and board has eliminated this issue. So, assembled board looks like:

How it's work? Watch it on Youtube:

https://www.youtube.com/watch?v=-Yzea2HfhkM




Design - VIAtronics 1.0 CART version
This is most flexible variant of VIAtronics! It may be use with any Atari XL/XE and probably with Atari 800 too. We (me and PTODT members) decided to make pretty looks board closed with modern cartridge and delivered to users with professional user manual. So, in case I spend much more time to arrange PCB layout...
The differences with VIAtronics 1.0 CART/ECI:
- lack of signals /IRQ and /RESET
- only D5XX addresses might be use.

I understand that some functionality was dropped but the CART version is still developers friendly without /IRQ and /RESET... don't forgot! Printing is the most important feature and it's the same as in previous version.


Completely assembled device: Possible case variants:
How it's work? Watch it on Youtube:

https://www.youtube.com/watch?v=57TVK9HEm9g


Design - VIAtronics 2.0 CART/ECI VERTICAL
Somebody ask me why not vertically version... well... my desk is big but somebody need to connect more than one device to CART/ECI slots...
Unfortunately under tests, the DB25 socket was too close to Atari case and it's rather not possible to use it with top case (without socket you can use it!). Additionally I found description issue... all issues were corrected and new PCB arrived (not assembled jet):
Additionally I added READ/WRITE indicators (I hope it work)



Design - VIAtronics 2.2 CART/ECI INTari
I hope, it's the last one project related to printing... This one is strange different.. it using Intel 8255 peripheral interface which contains three independently parallel eight bits ports without pull-up. There is most important, because you may use it with some devices like CH376 USB Host Controller. Of course printing(*) is possible as well. 8255 is cheaper and still available on many markets so it's good alternative for VIA6522.

(*) At this moment, Drukarz software can't print using INTari but it should be changed shortly.




Finally... whole VIAtronics family together
That's all. Have a fun prints!

Hi!

Our colleague @mono in cooperation with @atarifun made new very useful driver for VIAtronics (and JOYSTAR - very funny Centronics port based on Atari's joystick ports). In order to be fully compatible with this driver, easy modification should be made:

This modification adding data flow control between printer and Atari.