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View Full Version : IEEE 1284 parallel port and Propeller: Any past experiences?



AndrejaKo
10-27-2011, 09:51 AM
I'm thinking of using a Propeller to drive a IEEE 1284 which I'll use to drive a printer and a simple robot (not at the same time).

I'm interested in any past experiences with Propeller and parallel ports and if there are any special considerations that need to be addressed.

I'm already aware that I'll need to do voltage translation and I know what type of signals I'll need to send. I'll be using relatively short cables of less than 1 meter in length, so there shouldn't be much interference during transmission and I'll be using low data rates (I'm still not sure how low), so I don't expect much data loss.


Is there anything else?

Loopy Byteloose
10-27-2011, 02:10 PM
Much depends on what you really mean by IEEE1284 as it has 5 modes and can be uni-directional or bi-directional. Not all printers are the same in how much they communicate with a computer.

http://en.wikipedia.org/wiki/IEEE_1284

I suppose that if you build a single purpose device, it will be much easier to code.

AndrejaKo
10-28-2011, 06:18 AM
Well my idea is to implement all 5 modes eventually, but at first I'll just try to implement enough to produce output at the printer.

Dr_Acula
10-28-2011, 08:17 AM
Thinking simplistically, you need 17 propeller pins http://pinouts.ru/ParallelPorts/ParallelPC_pinout.shtml

For inputs to the propeller, use a 2k7 resistor in series and that will drop 5V to 3V.
For outputs, any octal buffer chip powered by 5V, eg HC or HCT series and that steps 3V to 5V.

So hardware will be simple.

For software, you could write some simple spin routines - eg "ToggleStrobe()" which toggles the strobe line. That is one that would be very useful. And "OutputByte" to put a byte on the data lines.

Maybe add a delay in "ToggleStrobe" as it might be a bit fast in pasm for old printers. But it probably will be ok in Spin.

Jack Hidley
12-24-2011, 04:46 AM
I have a very low speed (1-5Hz) data logging application where I plan on having some sensors connected to a Propeller. I need the Propeller to then send the data along to a PC. I'd prefer to use a USB port on the PC, but that is going to require more hardware, so isn't ideal. Serial is out, as almost no laptops have them anymore. This leads me to using a bidirectional parallel port.

Has anyone made any progress on using the Propeller to send data to a parallel port or possibly a USB port, through some other hardware?