Breakout board recommendations

[Clive S]

Then you are looking at either the opto board from DIYCNC, the £20 cheap board form Zapp, or what cnc4you are offering.
All are ok.
Then there is the support, i know you can get support from Roy at DIY CNC and also Zapp, but never bought anything form CNC4you.

Do any of those boards provide buffered signalling?

[magicniner]

What kind of buffering do you want?
Anything which can result in any variation to the relative timing of LPT pin signals being presented to the drives will mess up the part, there is no RTS/CTS handshake involved in the open loop with Mach3, the whole set up relies upon the data at the parallel port being presented almost instantaneously to the drivers, all timings are configured within Mach3 to work within the limitations of the system being driven.
External motion devices are fed move instructions via their plugins and can thus use buffering,
- Nick

[dodgygeeza]

Its a breakout board it will only be a simple buffering circuit, that gets the existing signals, cleans them up and duplicates them.

[GND]

Looks like we have three contenders - the HG08 from CNC4YOU, the ZP5A from Zapp and the Uniport from DIYCNC. Although it's the most expensive, the Uniport is currently my favourite from these as it includes a charge pump and two relays, plus opto isolation on the inputs. COmes in at £40 posted, so not too bad.

Anyone have any experience of using one of these in anger?

[cropwell]

If you want cheap opto isolation and a spindle relay then the Chinese BoBs like this one http://www.ebay.co.uk/itm/5-axis-CNC...item1ea10eaf6a which is "UK stock" seems a good start.

[dodgygeeza]

yes it looks like it.
The ZP5a and ZApp and the uniport are buffered.
The HG8 at cnc4You is opto isolated.

[magicniner]

I think they are all isolated and someone writing the tech specs hasn't read their digital interfacing text books ;-)

[GND]

Ah - something I can answer being an electronics eng by trade!

The buffering I need is really just signal conditioning - no significant delay, but beefing up the signal and the voltages from/to the PC port. Buffering in itsmore "IT" sense is where data is collected and delayed for some period, so allow streaming of things like video. Not something we want here, as you suggest!

My existing BoB has no buffering at all - just wired straight through - and that is what I'm trying to avoid again.