Re: EMC compatable computers

[Matt Shaver <mshaver-at-erols.com>]

On Friday 10 January 2003 12:20 pm, Phil Wilshire wrote:
> HI All
>
> I would think that Firewire would make a better option for a bus driver
> servo board.
> Any comments ???
> If you want a USB solution the 5272 Coldfire embedded system should work
> here.
> Again any comments ??

I don't know enough to comment whether 1394 has latency or frame rate 
problems like USB, but there are even bigger non-technical stumbling blocks:

1. The development kits I've seen cost $1500-$2000. See:
http://www.emjembedded.com/cgi-bin/america/setframe.cgi?spec+MDR

2. Firewire development is effectively a closed process controlled by the 
1394 Trade Association. Realistic participation requires becoming a member. 
Membership fees start at (you can see this coming, can't you...) $4000... 
every year!

The PPMC should be viable for a long time in desktop PCs with PCI parallel 
port add-in cards. If you want to develop a high speed serial controller, I 
think the best option is Ethernet. I don't mean a complete TCP/IP network 
device, more like a dedicated 100BaseT NIC connected to an embedded ethernet 
equipped servo controller through a crossover cable. The communications 
protocol would be raw frames (there's integrated hardware CRC checking for 
each frame). Inexpensive prototyping materials are widely available. As an 
example:

http://www.edtp.com/

Comments? Phil? Anybody? Don't all speak at once... ;) ,
Matt