Need Advice please: microcontroller with RS-232 Output

[Richard Henry]

I need some advice in designing a pushbutton interface to send commands via
RS-232 port.

I need to find a microcontroller that will take pushbutton inputs and send
the proper commands (Sony Protocol of remote-1) via RS-232 to a digital
video recorder board.

Any advice on the proper microcontroller that I have to use?

Thank's in advance for your help!

Alex

ELECTRICAL INTERFACE:
- EIA RS-422

DATA FORMAT :
- 38.4 kbps
- Asynchronus, full duplex communications
- 8 data bits, odd parity, 1 stop bit.

COMMAND BLOCK FORMAT
-------------------------------------------------------------------------- -------------------------------------------
| 1 byte | 1 byte | 1 byte
| n-2 byte | 1 byte | 1 byte |
| Bits 7-4 Bits 3-0 | |
| | |
|
-------------------------------------------------------------------------- -------------------------------------------
| CMD-1 | DATA | CMD-2 | DATA-1
| - - - | DATA-n | CHECKSUM |
| | COUNT | |
| | |
|
--------------------------------------------------------------------------

-------------------------------------------

As long as we are looking for interfaces, I need a micro that has a hardware
serial port on one side and an I2C bus on the other, and not much else.
I'll even settle for a non-micro dedicated piece of hardware (or hard-coded
micro disguised as a piece of hardware). Bonus points will be awarded for
including the EIA-232 (or even EIA-422) hardware drivers and receivers.

**Note** EIA (Electronic Industries Association) has replaced RS
(Recommended Standard) in the name of many standards. Don't fell bad if you
mixed them up - the Wikipedia article on EIA-422 starts out with "formerly
RS-422", but later makes a reference to "RS-232".

 

[Spehro Pefhany]

I doubt it.
The PIC hit #1 in volume in around 2002, and even then the 8051 was
well down the pack. It has been in continual decline for many years
now.

?? Could have fooled me. New devices all the time. They're like
roaches. Want a 100MIPS 8-bit processor with 12-bit ADC or an on-board
24-bit delta-sigma? Where's my PIC, dude?

Microchip should be able to carry their success in the low end (12-bit
instruction core) and their concentration (only one supplier as
opposed to a couple of dozen for the 8051 core) and their broad base
(lots of small companies and developers) to their 18 series and maybe
the dsPIC/24F, at least enough to make some good profits, but very
high volume will probably remain elusive.

Microchip has been doing some interesting business in low-end
"untested" parts for noncritical applications.

I think Atmel are now claiming the lead?

Atmel make one heck of a lot of AT89 flash 8051s. They are very
popular in Asia.

PICs are used extensively in smart cards too.

Dave

I mostly see 6805 and 8051s in 8-bit processor smart cards.


BUT:

---> ARM is the new 8051 <---

 

[John B]

..
..

As long as we are looking for interfaces, I need a micro that has a
hardware
serial port on one side and an I2C bus on the other, and not much else.
I'll even settle for a non-micro dedicated piece of hardware (or
hard-coded
micro disguised as a piece of hardware). Bonus points will be awarded for
including the EIA-232 (or even EIA-422) hardware drivers and receivers.

**Note** EIA (Electronic Industries Association) has replaced RS
(Recommended Standard) in the name of many standards. Don't fell bad if
you
mixed them up - the Wikipedia article on EIA-422 starts out with "formerly
RS-422", but later makes a reference to "RS-232".

An Atmel ATmega8 should do trick. Plenty of software on:

http://www.avrfreaks.net/

amongst others.