Hi everybody, after I tried over months to subscribe to both lists I'm now finally subscribed to cctalk at least. I don't know if it's usual or not to write an introduction but I'll just do so by keeping more an eye on the computer system I own. If you don't care just skip this mail ;) As my From header states my name is Oliver, I live in germany and right now I'm 27 years old. That should be enough to my person - now let me tell you a bit more about the computer system I own ;) EAW P8000 This system was built between 1987 and the breakdown of the former GDR - the eastern part of germany - 1990. The system itself is split up into two "towers" connected together. The first tower called "P8000 Computer" contains a 8Bit system (Z80) and a 16Bit system (Z8001).The 2nd case - the "P8000 Winchester" - contains a Winchester Disc Controller which runs with a Z80 CPU and is connected to the 16Bit part of the "P8000 Computer". Up to three MFM drives (all with the same geometry while the geometry itself can be configured) can be connected to the WDC. The 8Bit part is built on a single board, has 64KB SRAM, 2 SIOs to connect up to 4 terminals to it, one PIO to connect a EPROM programmer, and one PIO to establish a connection to the 16Bit part. It has 2 5.25" floppy drives with an external connector to connect two further 5.25" or 8" floppy drives. The systemmonitor is loaded from two 2732 EPROMs. The system originally supported three operating systems while two survived the time being. I own UDOS which is a Z80-RIO clone and OS/M which is a CP/M clone. There also was an OS called IS/M which was an ISIS clone. The more interesting (at least for me) part is the 16Bit part. The 16Bit part is built on a single board too (6layer) while the DRAM are single board which can be hooked up onto the mainboard. The system runs a Z8001 with 3 MMUs and Z80-peripherial ICs (PIO, SIO...) It also has 2 SIOs for 4 terminal connections, and one PIO to connect the WDC. The system also has two furhter PIO chips to establish a connection to the 8Bit system. The system runs with up to 4MB of DRAM but it might run with more RAM with self-made RAM modules. There exists also a RTC for the system and an extension to connect an 80286CPU + 1MBRAM to the 16BIT port to run a x86 OS on it while stearing it from the OS running on the 16Bit system. The Operating-System running on the 16Bit part is WEGA - a ZiLOG ZEUS clone. To boot WEGA at first the 8Bit system has to be booted up with UDOS (the Z80-RIO clone) to load a communication software which handles the communication over the 8Bit-PIO. After this is done the system switches over to the 16Bit system and the system monitor there gets loaded. The WEGA-Kernel (most parts are still original ZEUS objects) itself has the corresponding part for the 8<->16Bit communication interface in it. This was done to get access to the floppy drives, the EPROM programmer and the 4 8Bit-terminal connections which are all connected to the Z80 on the 8Bit-system. To access for example a floppy, the WEGA-kernel has to send the request using the PIO connection to the 8Bit system which handles it and sends the results back to the WEGA-kernel on the 16 Bit system. Same goes with the WDC which is connected through another PIO directly to the 16Bit system - command codes are sent to the Z80 on the WDC which handles the codes and sends the results back to the 16Bit system. Not that fast but it works good. Pictures and so one are all collected on my homepage http://pofo.de/P8000/ while most (if not to say all) of original documents are written in german... So - what do I do with the system? I use it for learn more about hardware processes itself, assembler and to get a deeper UNIX knowledge which is easier to start with there then with todays UNIX systems. Las project was to get TCP/IP working and I successed by usingg K5JB to get FTP and ping to work via SLIP. Because the speed was damn slow (and not just because of the baud rate), I came to the conclusion that a better performance could be achieved by implementing TCP/IP in the kernelspace instead of having it run in the userspace. So my goal is now to get the kernel sources right now to make the neccessary changes to get TCP/IP running in the kernel. As you might think now this is not so easy as it sounds. The sources for some objects of the kernel survied over the time, but many are missing. I'm now sitting here since a month disassembling the original kernel object and writing the disassembled code back in C. I've started this by having lets say nearly-to-zero ASM knowldege and I'm making good progress. Only some objects are left. From time to time the C files are not compiling to exactly the same object which is in the kernel. Some times other temporary registers are used for operations and so on. I'm trying to get 100% the same object to be 100% sure I have the same code the object was built with. The compiler on that system should be the same but of course I can't guarantee for sure. So - I'll probably ask some ASM<->C questions on cctech when I'm subscribed successfully (or I'll write and read the answers in the archive) hoping that there are still people alive being able to help me ;) Until know I had to find out that none was able to help me when I asked my ASM-C questions so I had to help me always by my own (which costs sometimes a great deal of time.... *sigh*). So far - greetings, Oliver -- Oliver Lehmann http://www.pofo.de/ http://wishlist.ans-netz.de/