| ??? 09/03/04 19:32 Read: times |
#76856 - RE: Defining the project & new ideas Responding to: ???'s previous message |
We can, but then it won't be able to do much else. My basic idea is 4 '51s: CPU, Audio, Video and I/O. All of them will be loaded nearly 100% when performing their respective functions. That's more chips than I thought we'd use, but if we need a dedicated chip for audio that's fine. Of course if we have a dedicated chip for audio we can have lots of audio channels. :) 4) Again, the question whether we use different derivatives for different components, or all the same. If so, a single USB-enabled chip i.e. for IO would be nice, and I DO mean slave chip - i.e. for syncing with PC, network connectivity etc. This is completely optional though. We can have that as an option. I developed a keyboard controller based on a TI 8052 core that had USB. I *thought* it had master capability and as a consequence I thought others would too. But if Erik and you are sure that that's not available then that's one less thing to do. It's been a long time since I worked with that TI part so maybe I'm wrong about it supporting USB master functionality. 5) With separate chip we could make several options. The basic idea is your bulk storage is a PC (over RS232/USB) and your "current" storage is some built-in eeprom/flash/NVRAM. The "advanced" idea is to give it ability to use harddrives and floppies, and whatever you desire. I believe the basic unit should have some mass storage, be it IDE for a hard drive or an SD or CompactFlash port. I want the unit to be as stand-alone as possible with the PC only being used to get programs to the unit initially. Since USB isn't possible we should at least consider the possibility of including Ethernet to make it even easier to get data on/off. Or we could just depend on RS232 to move data between the PC and the unit. 6) 2 joystick ports: Absolutely yes! :D Optionally one/both mouse-enabled :) And since it would be rather hard to get any other kind of keyboard at reasonable price attachable with reasonable easiness, PS/2 is the way to go. A PC-style parport and 2 serials if we aren't short on pins with the IO chip (IDE swallows quite a few, and we still need a common address and data buses! Agreed. Also, in my opinion, we should (once specs are defined) choose a single derivative and use that for all 2-4 MCUs on the board. Unless we run into a technical reason why we should use different derivatives I'd prefer to have them be the same. It just seems like it'd be easier to get 4 of a single chip than 1 from this manufacturer, 2 from that, and 1 from another. Regards, Craig Steiner |
