AVR-Chat

On Mar 31, 2006, at 6:35 AM, Kathy Quinlan wrote:

> If I was to release and SBC that has the following, what else would  
> be good.
>
> SPI with 16 chip selects.
> Ethernet 10BaseT (100BaseT could be done, but was not needed on  
> this design)
> 32K sram
> 128K Flash ROM
> LCD PORT
> 1x RS232 Port.
> On board 5V reg.
>
> Connectors for both ISP and Jtag.
>
> Spare pins routed to a connector (7 pins on various ports)
>
> Main Xtal 14.7456Mhz
> RTC xtal of 32.768Khz.
>
> Anything else ??
>
> Just have designed this for a customer, but they think it would make a
> good SBC, and are prepared to sell these to the community.

What Ethernet chip are you using? I've been looking at the very cool  
ENC28J60 from Microchip (an SPI-interfaced 10BaseT standalone  
Ethernet controller with PHY, MAC, buffer, etc.)

Note that Futurlec may soon come out with something very similar very  
soon now, based on an email from them.
I had suggested an Atmega version of their Web Control Board:
http://www.futurlec.com/Web_Control_Board_Tips.shtml
and they said that sounded like a good idea and they would do one.
I don't know what shape it will take, though.

Also, this sounds much like the Ethernut board:
http://www.ethernut.de/en/hardware/index.html

Anyway:

- Assuming you're using a Mega128, having provisions on board for the  
use of an AT90CAN128 (i.e. provide for a standard footprint 8 pin CAN  
transceiver, (jumperable) termination resistor(s) and 3- or 4- pin  
connector to be added) would be interesting.

See the Atmel CAN adapter board datasheet for useful info and schematic:
http://www.atmel.com/dyn/resources/prod_documents/doc4330.pdf

- Provisions for big (4Mbit?) SPI flash chip for data logging, etc.



-- 
Ned Konz
MetaMagix embedded consulting
MetaMagix@gmail.com