From mboxrd@z Thu Jan  1 00:00:00 1970
From: Sebastian Frias <sf84@laposte.net>
Subject: Re: True Parallel Port Interface for Bit-banging?
Date: Tue, 25 Oct 2016 16:56:47 +0200
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 <580F6A1D.4000409@laposte.net> <20161025142935.GA2875@katana>
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To: Wolfram Sang <wsa@the-dreams.de>
Cc: Sudip Mukherjee <sudipm.mukherjee@gmail.com>, linux-parport@lists.infradead.org, philb@gnu.org, tim@cyberelk.net, Jean Delvare <jdelvare@suse.com>, linux-i2c@vger.kernel.org

On 10/25/2016 04:29 PM, Wolfram Sang wrote:
>> The virtualisation idea is not good then?
> 
> It is not that. I think good old DOSEMU could do that. Bit-Banging ports
> can be timing critical, though, and in this department virtualization
> solutions often fail.
> 

Thanks.
I understand your point, but I'm guessing that the big-banging routine (or the
protocol to be used) should be time-independent in order to run on different
real HW PCs, right? Otherwise a 386DX and a 486DX2 could behave differently,
right?

Or is the "timing issue" you talk about more related to unpredictable
latencies due to the way the SW virtualisation works?

What about emulation? Do you think emulation would be more predictable?