[comp.sys.amiga.hardware] Serial Port, SYNC mode?

maniac@lil-ed.cs.unlv.edu (Eric J. Schwertfeger) (10/01/90)

	I'm hoping that someone out there can answer a question 
for me.  Can the standard amiga serial port, either through 
the serial.device, or through direct hardware access, do
8 bit syncronous transfers, with no start or stop bits?
I don't think this can be done, but I'm willing to listen
to anyone with an idea.

	The reason I ask is because I'm toying with the idea
of writing an mnp.device, which will add mnp error detection 
and correction protocols to terminal programs transparently.
The problem is, MNP level 3 requires syncronous comunications,
and MNP level two only has an efficiency of about 84% if I
remember right (MNP 3 gets 108%).
 
Eric J. Schwertfeger, maniac@jimi.cs.unlv.edu

jms@tardis.Tymnet.COM (Joe Smith) (10/07/90)

In article <2024@jimi.cs.unlv.edu> maniac@lil-ed.cs.unlv.edu (Eric J. Schwertfeger) writes:
> Can the standard amiga serial port, either through 
>the serial.device, or through direct hardware access, do
>8 bit syncronous transfers, with no start or stop bits?

From the RKM Hardware Manual: "Data will be moved out of the shift register,
one bit during each time interval, starting with the least significant bit.
The shifting continues until all 1 bits have been shifted out.  Any number
of combination of data and stop bits may be specified this way."

But there must be at least one stop bit.  If you load the registers with
all zeros, no data will be sent, no interrupt will be generated.

The Amiga's built-in serial port does not support sync.

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ben@epmooch.UUCP (Rev. Ben A. Mesander) (10/08/90)

>In article <1277@tardis.Tymnet.COM> jms@tardis.Tymnet.COM (Joe Smith) writes:
>In article <2024@jimi.cs.unlv.edu> maniac@lil-ed.cs.unlv.edu (Eric J. Schwertfeger) writes:
>> Can the standard amiga serial port, either through 
>>the serial.device, or through direct hardware access, do
>>8 bit syncronous transfers, with no start or stop bits?

[details from the hardware RKM deleted]

>
>The Amiga's built-in serial port does not support sync.
>

If I remember right, there's a serial port of sorts on each of the CIA's.
One is used for the keyboard, the other comes out as one of the pins on
the parallel port. Is it possible to program these to run in syncronous
mode?

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