Interfacing 8085 Microprocessor with Laser Printer

Hello, ajay2121988

You've missed out a bit of essential information - what kind of interface does your printer have? Parallel (AKA "Centronics"), RS232, USB, other?

Firstly,I thank you for your response.The laser printer available with me has the usb interface.please provide me the circuit diagram with a complete "how to do" procedure or refer to me some book in which i can find the abovesaid details.

Sorry to bring bad news. I may be wrong, here, but I think this is a bit of a non-starter, as the 8085 would have to be a USB host (or master), rather than a slave (which is relatively easy).

Alright,so can you tell the requirements for the completion of this project?Please do correct me if I am somwhere going wrong in my concepts.I will tell you the approach I have followed till now for the project.If you feel the approach is wrong,or even total rubbish,then please tell my mistake or suggest something useful:-

1)I had the PCB oriented diagram of the interface circuit(which you can easily find online.Its from EFY volume22,a book titled electronic projects), seeing which I tried to hook up the circuit on the breadboard in order to test it.However,I discovered that converting a PCB oriented circuit into a circuit suitable for testing by the means of breadboard is real tough and involves a lot of connecting wires, 2 7407ICs and a 12-resistor network with a LED to test the output.

2)based on the input table as given in the abovesaid publication,I gave an input and was checking the output(a control word of value 10H) with the help of LED.However,the board has become toally entangled with wires and now I am facing problems with d.c. power supplies.

3)My first aim was to test the printer interface circuit (in which till now no success has been achieved),since if this circuit does not work,its a wastage of time to think any further.

Hoping for a positive response,

Regards.

Can you please post a link to the circuit? (You can just copy from the browser address bar and paste into your post). I got onto the EFY site, but couldn't find the referenced circuit. If you give us a link, I'll have a look.

The link is:

books.google.com/books?isbn=818815217X...

you can also get to it by going for google search and typing the following:

"EFY volume 22 interfacing microprocessor 8085 with printer".On following this procedure,you get the link required on the top,first in order in the following format:-

Electronics Project Volume 22 - Google Books Result

by EFY Enterprises Pvt Ltd
The 8085 microprocessor is interfaced to the printer through 8255 ... between 8255 and the printer should be connected as show in Table 1. (EFY Lab note. ...
books.google.com/books?isbn=818815217X...

I hope this helps.

Thanks.

Ok, thanks for the link.

As I suspected, this circuit is designed with a parallel (Centronics) type interface. Sorry again, but I don't think you'll get anywhere with a USB printer.

Ok, I will try to arrange a parallel(Centronics) type interface, but till now I had been trying to build the interface circuit with the help of Fig.4 and Fig.5(component layout for the pcb) on the breadboard which lead me to the problems as described before.

I have 2 doubts.

1)Is it a correct approach to build the circuit on breadboard (for testing purpose) just by following the Fig.4 and Fig.5 or a proper circuit diagram is needed?

2)Is there any way in which I can convert the abovesaid figures into circuit diagram?

Above all, can this circuit be tested on the breadboard?If not please suggest a way of testing this circuit.

As you know, the EFY article only describes the interface circuit:

I assume you have the 8085, 8255, etc. built as a separate assembly - maybe a development board/kit(?) - as shown in the block diagram, fig. 2 of the article.

Breadboards rapidly get out-of-hand, turning into a birds-nest of wires that is very difficult to work with.

I'd suggest laying out the components on a piece of matrix stripboard (e.g. Veroboard). You can download a good layout program from:

http://www.heyrick.co.uk/software/verodes/

Good luck,

John

hey i too struck out wit the same project but my problem is that i have the centronic interface and the interfacing circuit in a pcb board but the connection between them is the only problem

It has been a while ago (+-1985) I used an 8155 next to the 85 and it handled all the printer bus protocol. If you know the printer commands (PCL) you can produce some fine printouts.

If you need USB there should be nice USB chips available . USB - anything converters are also freely available.

INTEL is about the best source for info. (cookbooks & product specs) My manual is dated 1979. If I can find it I will post more data.

8085？ who still use it? is it still bought on the market?