> >>> James> Yes, but a video board is a slave system, it must do what the main > >>> James> system requires. > >> Does it need to be able to function as the only video board on the system? > > > > The Ethervideo box isn't a "video board", it is more like an X11 terminal. > > > It could be an X terminal, or not. What is apparent is that there are > clearly two cases here. > > 1. The box can function as the video card for a PC. In this case, > Ethernet is functioning as just a fast serial interface and would be > connected directly to the PC's Ethernet connection with a RJ45 cable -- > like my DSL box is connected. Or, could it simply respond to any > address if the senders IP address was 127.000.000.xxx? But, that might > be a security issue on a network. > > 2. The box could function as a video display on a network. It would be > reached by a router or coax. In that case, it would not act as the > primary display for a PC.
A computer doesn't need a video card, at least I've never seen one that did. It does need a console. Which can be a window on an X terminal. The user can easily set IP addresses on an X terminal, as it has display and keyboard (and mouse or other pointing device). The trick will be to find a good way to set the IP addresses on the computer before the console connection to the X terminal is established. We can't assume that the system supports an open bios, or has a socket for additional BIOS. Most pee-cee type computers will likely need a card with a socket for BIOS. Once we do that we might as well put an Ethernet port on the card, and some SATA ports and maybe an RS-232 port or 2. (And anything else that is inexpensive and recent computers don't have enough of.) We could include a bunch of jumpers or dip switches or rotary switches or whatever for the Ethernet addresses. We'd need at least the computer's IPaddr, the IPaddr of the Ethervideo/X11 box that will be the console. Maybe the netmask and gateway. > > So, how would the VGA-to-X11 bios firmware know what IP address to use for > > itself? > > How would it know the IP address of the Ethervideo box that is its console? > > Well, my DSL box has a fixed IP address. Doesn't a slave device have to > use a fixed, or hardware selected, IP address? I suppose if your ISP provides static IP addresses, they could just hardcode the address into the box somehow. But ISPs are a special case, we can't dictate IP addresses. > I suppose that the box should have an IP address so that a small local > network was possible even in case #1. However, I really think that a > network port dedicated to only the console display is the best idea for > case #1. That's up to the end user. They might already have a single cat6 in the walls and not want to run more cable. > > Will it ask the Ethervideo box to create a new window (like xterm -C)? > > > No, it would be functioning as the whole display in VGA BIOS mode for > boot and would be controlled by a driver after that. What it would do > after boot would be totally controlled by the driver and the software > using the driver just as it is with any other video card. It isn't a video card. It is an independent node on the Ethernet. > IIUC, what you are talking about is having a virtual (non-hardware) > replacement for a KVM switch. This could work with a box that had a > CPU. This is an issue that would need further consideration. At least some of the SOCs include small CPUs. I'm not sure if a pure DSP could run X or not? > > We need a way to configure this stuff and avoid chicken-and-egg problems. > > Fixed (hardware settable) IP addresses should avoid bootstrap (chicken > vs. egg) issues. If the box (with a CPU) needs to know the IP address > of the network administrator then you would have to have persistent > memory for that. If the box needs to be configured, then the network > administrator would have to configure it before other PCs on the network > were started. With a box that has a CPU (probably running X11) it might > be a good idea to have a flash card to store various data such as IP > addresses. Yes, we need at least enough nonvolatile memory to store IP addresses, and there are likely to be some configuration options to store. Might want enough to store codecs. > I was thinking in terms of connecting my TV to my home network. Exactly, that's a significant use for the box. > I think that I am suggesting that two models would be a good idea for > the two different cases although one that could do case #2 should also > be able to do case#1. The more advanced (#2 model) would have a CPU, a > flash card socket (this means that it could be configured by storing > data in the card on PC) and could run X. The simpler model would not > have a CPU and might have a hardware settable IP address. Although if > we used a chip that directly supported a flash card and had a MCU, a > flash card might be the best way for the non-CPU box to be configured. > Clearly, there are various possibilities to address these issues. Two models? Ugh, we're having a hard enough time getting one going, and now we have this optional card with bios socket and stuff. Two different models will increase the manufacturing costs (unless someone thinks we can sell gazillions of these things?). If there is no CPU, how do you get data from the Ethernet port to the decoding hardware? Is there a variety of flash card or similar device that the box could write IP addresses to, then the memory gets moved to the bios card? And be inexpensive enough? Maybe the box could update the card's bios that way as well. I suspect most people would prefer this over a gazillian dip switches. If we are clever, perhaps we could use the same socket for the box's firmware, making it easy to safely update the box's firmware while keeping a known good backup. Do we have a good candidate for the decoding chip? If so can it run an X11 server or would be have to add a CPU? I'm assuming that enough CPU to run a X server wouldn't cost much these days, but it would be better if we can keep the costs as low as possible, _______________________________________________ Open-hardware-ethervideo mailing list [email protected] http://lists.duskglow.com/mailman/listinfo/open-hardware-ethervideo
