UART In the new design

[Naimesh]

Hello,

I am doing one new design with 186 processor and I want a serial port
on the board.

Please suggest any UART for that.

I have used 8251 before in older design but was worried about
availability because that is a old part in DIP package. Any 8251 pin
comapatable devices in SMD package.
Thanks for the suggestions,

Naimesh

 

[Roger Hamlett]

"Naimesh" <naimesh.thakkar@gmail.com> wrote in message
news:1103286774.803749.27300@z14g2000cwz.googlegroups.com...

Hello,

I am doing one new design with 186 processor and I want a serial port
on the board.

Please suggest any UART for that.

I have used 8251 before in older design but was worried about
availability because that is a old part in DIP package. Any 8251 pin
comapatable devices in SMD package.
Thanks for the suggestions,

Naimesh
What other 'support chips', are you likely to need?. There are a lot of

'all in one' chips available, that give you some programmable I/O, timers,
UART etc., in a single chip. If you need more than just the UART, it might
be worth considering one of these.

Best Wishes

 

[Tim Wescott]

Naimesh wrote:

Hello,

I am doing one new design with 186 processor and I want a serial port
on the board.

Please suggest any UART for that.

I have used 8251 before in older design but was worried about
availability because that is a old part in DIP package. Any 8251 pin
comapatable devices in SMD package.
Thanks for the suggestions,

Naimesh

How about the UART that comes on most 186 parts these days?

The 8251 is obsolete, unless someone's taken it up again -- probably
because everything under the sun has a built-in UART these days. The
last time I had to do a search the only thing available was a Philips
part and their peripherals are _twisted_.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

 

[Markus Mandl]

Naimesh schrieb:

Hello,

I am doing one new design with 186 processor and I want a serial port
on the board.

Please suggest any UART for that.

I have used 8251 before in older design but was worried about
availability because that is a old part in DIP package. Any 8251 pin
comapatable devices in SMD package.
Thanks for the suggestions,

Naimesh

As Tim pointed out, finding something dedicated might be difficult.
You could also glue a 89C2051 with a small CPLD to your 186. Might also
be cheaper.

Regards
Markus

 

[Nicholas O. Lindan]

"Naimesh" <naimesh.thakkar@gmail.com> wrote

I am doing one new design with 186 processor and I want a serial port
on the board. Please suggest any UART for that. I have used 8251

Along with the suggestions of high-integration '186 uPs and the 16550
you might want to try the 2651 family.

I would contact the mfg. before design-in to make sure the part is
not scheduled to go down the tubes in the near future.

Parts with high military usage often stay around for a long while.

--
Nicholas O. Lindan, Cleveland, Ohio
Consulting Engineer: Electronics; Informatics; Photonics.
Remove spaces etc. to reply: n o lindan at net com dot com
psst.. want to buy an f-stop timer? nolindan.com/da/fstop/

 

[Adrian Jansen]

Naimesh wrote:

Hello,

I am doing one new design with 186 processor and I want a serial port
on the board.

Please suggest any UART for that.

I have used 8251 before in older design but was worried about
availability because that is a old part in DIP package. Any 8251 pin
comapatable devices in SMD package.
Thanks for the suggestions,

Naimesh

I use the MAX3100 UART for this sort of add-on. Needs SPI bus to

operate, but thats pretty standard on most controllers. May not be
available on a 'bare' 186 processor.

--
Regards,

Adrian Jansen adrianjansen at internode dot on dot net
Design Engineer J & K Micro Systems
Microcomputer solutions for industrial control
Note reply address is invalid, convert address above to machine form.

 

[Kryten]

"petrus bitbyter" <p.kralt@reducespamforchello.nl> wrote in message
news:u_Ywd.115198$lN.104855@amsnews05.chello.com...

In the old days of the first IBM PCs the 8250 was chosen. It was said
almost obsolete but it was used in AT's as well. It was a horrible thing
as there were lots of small differences between manufacturers and series
and a lot of them were also buggy. New, compatible UARTS were developed
and the 16550 is the last one in these series. AFAIK it is stable and bug
free. It is sold as PC16550D (National), SC16C550B(Philips),
TL16C550(Texas) and some more. At least the Philips version comes in
packages DIP40, PLCC44 and LQFP48. Some google for the datasheets will
learn you more. Hardware interfacing will hardly differ from the 8251.

I can believe they are stable, but I heard the classic PC COM port doesn't
do hardware handshaking correctly. I can't recall the details but I'm told
it was a known problem but nobody would fix it for fear of incompatibility
problems, and that there are software kludges to tackle it.

RS232 ports are disappearing from the desktop. Has the OP considered a USB
chip? I've just used a chip from FTDI and it makes interfacing even easier
than a UART chip. No pesky baud rates for example.

K.