On Wed, Sep 25, 2019 at 8:02 AM ZB <zbigniew2...@gmail.com> wrote: > On Wed, Sep 25, 2019 at 12:05:04AM -0700, Ralf Quint wrote: > > > These are two totally different worlds! The only way you could get FreeDOS > > to run on a RPi is after installing one of the default Linux versions to > > install QEMU, which is an x86 emulator and install FreeDOS within that > > virtual machine. Again, FreeDOS can NEVER run natively on a RPi... > > With DOS it would mean too much work - but I believe a group of determined > coders could be able to port, say, CP/M. Of course it would be "CP/M-like" > OS for RPi rather than "strict port"
And who, precisely, would do this? This is another instance of stuff that has come up before, with a desire for support for things that didn't exist when DOS was still sold and supported. It might be theoretically *possible* to do it, but the folks with that level of skill will be professional developers who get *paid* for writing code. I don't see folks who *can* do it investing the time and effort for free, when the time and effort could be applied to work they got paid for. > Why would they do that? To create much simpler OS for RPI than Linux. Who > needs that whole complexity on such little SBC? CP/M would do just fine. No, it wouldn't. Digital Research developed CP/M as an OS for 8 bit micros like the Intel 8080 and Zilog Z80. They were single tasking CPUs supporting a whopping *64K* of address space. OS, applications, and data all had to fit into 64K. The Raspberry Pi uses an ARM Cortex CPU, with a 32bit address space and a multi-core design. It can run a full multi-user, multitasking OS like Linux, and does. And ARM CPUs are often used in Internet of Things devices. The critical point is the the CPU can run a full TCP-IP networking stack, and become a node *on* the Internet. A second critical point is the the costs of such CPUs have dropped to the point where you *can* affordably use something like a a 32bit ARM CPU in an embedded device. Who needs that complexity on such a little SBC? We do. You can actually run a full Linux distro and Linux apps on a form factor the size of a cigarette pack, and people are. Everything gets smaller, faster, and cheaper, and what can be done expands in consequence. CP/M is *too* simple, designed to work on vastly less powerful hardware. As an example, early versions of DOS supported Ctrl-Z as an EOF marker. This was inherited from CP/M, because up till CP/M 3.0, the *size* of a file was not specified in a directory entry. The OS needed a marker to indicate where the file *ended* when it was being loaded from disk. IIRC, it wasn't till MSDOS 5 that that "feature" was deprecated and I could stop trying to tell things like editors that an embedded ^Z was *not* an EOF marker. And even if $DEITY works a miracle and someone appears to port CP/M to the ARM architecture, then what do you do? What will run under it? Who will port existing CP/M applications to ARM as well, or write new ones? If you are savvy enough to try to get FreeDOS running under an emulator like QEMU on a Raspbery Pi, that "simplicity" of CP/M doesn't buy you anything. > As Chuck Moore (Forth creator) once said: "most computer operating systems > devolving to caveman interfaces ("point at the pretty pictures and grunt")" And there are folks who want to do precisely that. Those aren't *my* use cases, but so what? Computers are tools people use to do work or play. I don't get to decide whether their uses are acceptable, and wouldn't want to if I could. > regards, > Zbigniew ______ Dennis _______________________________________________ Freedos-user mailing list Freedos-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freedos-user