data sheet of dsp ti-54x series
Hi my_garden,
I don't know, why you are interesting from RJ0XX...
I didn't read the data sheets, but what you think about
a chip, which manufacturer don't produce it...
First my opinion is that it's a SHIT...
I'll say you a similar example with me...
I had a device with a chip HC4 PCI-to-ISDN Controller
from HiNT before 1 year... Before some months I found
their site and noticed, that there aren't .pdfs for HC4
There are only info about their new products...
I mean HB4 family (misc PCI Bridges)... I wrote a e-mail
and they told me, that it's a old chip, which they don't
support, and they hadn't data sheets...
BUT what's happen... I have a device with their HC4,
and they havn't data sheets... What is this shit?
Huh... The situation is similar!
BTW, now I'm thinking about a project, which I can
describe as Ethernet_To_E1_bridje. This is not easy
project, you know! There aren't universal and perfect
converter! And Ethernet To E1 is very relative term...
The device can works as a special router with own
MAC address and IP, or only converter from Ethernet
to E1.
1. In first case the device must do Network
Address Translation. The device must recognize
IP, TCP, UDP, ICMP, ARP and RARP packets and modify
it, not only for NAT, but to change TTL and so on...
It's not a big problem, but...
But what do you think about ARP requests? What do you
think will happen, when you have 100mbps Ethernet and
2mbps E1 with speed ratio 50:1? huh...
I suppose, that you want to say me: "The protocols
from the upper levels are interesting from this!
What you mean?"
2. In second case the device must convert and
transmit (receive) only Ethernet packets. Ethernet
NIC chip must work in promiscious mode and the
device must operate only to retransmit with incoming
MAC addresses. One of the difficult questions is:
"How long is buffer lenght? Case with 1 Eth packet
is not best, coz you will have many lost packets.
buffer with lenght 1GB is not perfect, coz you
will have terrible performace if there are hackers
or flooders... I can't say how long buffer must be...
Similar problems are examined in
<telecom-traffic_designing>... blah... blah... blah...
The device <Eth 2 E1> must support flexible
configuration, coz some devices in telecom way can
modify the flow... DEvices as digital switch and so on...
can modify not only 0 and 16 timeslots... blAH... blah..
So... you'll spend a lot of your time for this relative
project...
But it's great to use telecom network and all telecom
equipment to make large LAN. I mean LAN, not WAN or
inet...
))
I don't offer you Mitel or Realtek. I wrote them for
example... I can find and buy Mitel (now Zarlink) MT9075
and have some pcs RTL8019AS. All devices from Realtek are
not best Eth NIC. But you can order and buy them...
I think that Mitel is one of well known manufacturer
in PDH Telecom area, in SDH and SONET may be Ubicom
and some others os the best...
))
feel free to disagree!
Wazard Dreamer