FS-UAE serial and parallel port emulation

[Kellogs]

Dear all,

We bought a professionnal oven of the 1990s, which is controlled by an Amiga computer 2000 but is compatible with 3000. The link is done with two cables, one parallel cable and one serial cable.

What is the state of support for parallel and serial port in FS-UAE? We read that parallel is now supported in Linux hosts (which is our case).

Do you think FS-UAE can provide a good emulation?

Kind regards,
Kellogs

[FrodeSolheim]

Hi, FS-UAE does not support using real parallel ports. I'm not sure about the status in other UAE versions.

Hooking up to a real serial port might work on Linux, you'll have to test and see if it works.

[Toni Wilen]

It most likely won't work. Parallel port hardware is too different. Only guaranteed working solution would be custom hardware that has USB (for example) on other end and 25-pin parallel port on another end that allows software bit banging of all pins that Amiga can also control

PC parallel port is not as flexible as Amiga port. All Amiga parallel port data pins and other pins (pout,busy,select) can be separately programmed to input or output mode. PC parallel port all data pins are either input-only or output-only. Pout,busy,select data direction can't be changed.

PC serial port is nearly fully compatible, only exception is 9-bit mode (1 start + 9 data + 1 stop bit) which is not supported by standard PC serial port hardware.

[Kellogs]

I read this message post, which indicates that a fork of FS-UAE supports virtual parallel port: http://lallafa.de/blog/2013/05/emula...x-with-fs-uae/

PC parallel port all data pins are either input-only or output-only

Bidirectional ports are supported in Linux kernel versions 2.2.5 or later.

Any idea if this modification was added to the dev release?

[FrodeSolheim]

Toni refers to that on PC hardware, all data pins are - at the same time - either input or output . So yes, the data pins are bi-directional, but not *individually* bi-directional.

The virtual parallel port by lallafa, while looking very nice for hooking up external software interfaces to FS-UAE / Amiga parallel port, won't really help for native parallel port access (even if the PC hardware was capable I mean).

[Kellogs]

Originally Posted by FrodeSolheim

Toni refers to that on PC hardware, all data pins are - at the same time - either input or output . So yes, the data pins are bi-directional, but not *individually* bi-directional.

I guess you are right. I am playing around with a CNC driven by LinuxCNC and configuration goes like this : some pins are output, others are input. But not all are either input/output.

Are you sure this is a controller restriction under a PC?

Dammed! This means I wight be obliged to work under the original hardware, which is becoming rusty and needs a detailed analysis.

For example, the Amiga 2000 has a hard disc (IDE) but it seems dead. On the converse, I have 3 controllers as spare parts. Can I buy an old IDE disc and plug it in?

[Kellogs]

Apparently, a compatible parallel port already has been implemented (in parts) as an Arduino.

https://github.com/cnvogelg/plip2slip

Faster speeds could be achieved by using a PLIP (parallel port IP) device that
uses the parallel port to transfer IP packets to another host. Since the Amiga
parallel port is fully bi-directional you can use a half-duplex protocol and
then transfer an IP packet byte-by-byte over the port. This is done in the
magPLIP driver available on Aminet[1]. Unfortunately, this approach requires
an Amiga or another Computer with a fully bi-directional port on the peer side.
With this parallel approach you can achieve up to 15-20 KiB/s transfer speeds.

The idea in this project is to use the custom I/O ports of an AVR microcontroller
board (here an Arduino 2009) and implement the parallel port there. The mcu
implements the magPLIP protocol and can then receive and send packets to/from
the Amiga.

I guess also more advanced professionnal parallel ports are available under a PC, for industrial. Will look into.

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

Byte Mode, also known as "Bi-Directional" (although all modes except Compatibility Mode are in fact bi-directional), is a half-duplex mode that allows the device to transmit eight bits at a time using the same data lines that are used for the other direction. This mode is supported on a minority of pre-IEEE-1284 interfaces as well, such as those built into the IBM PS/2 computers; because of this, it is sometimes unofficially called the PS/2 mode.

I also got this information from the Amiga OS wiki:
http://wiki.amigaos.net/wiki/Parallel_Device

Also, derivates standards:
RS-422/RS-485 wikipedia

http://en.wikipedia.org/wiki/RS-422
http://en.wikipedia.org/wiki/Rs_485