Re: P112 Floppy Controller
On Sat, 23 Apr 2022, Craig Ruff via cctech wrote: The P112's floppy controller is the one in the SMSC FDC37C665IR SuperIO chip. The data sheet states it is a 2.88 MB "Licensed CMOS 765B Floppy Disk Controller" and claims 100% IBM compatibility (for what that's worth). 2.8M (it is not "2.88" unless MB is 1024,000) means that it includes a 1000K data transfer rate 765B means essentially the same FDC as PC (NEC 765 based) Does it also support FM? 125K data transfer rate (TRS80, Early Osborne)
Re: P112 Floppy Controller
The P112's floppy controller is the one in the SMSC FDC37C665IR SuperIO chip. The data sheet states it is a 2.88 MB "Licensed CMOS 765B Floppy Disk Controller" and claims 100% IBM compatibility (for what that's worth).
Re: P112
On 12/3/19 11:00 PM, Lamar Owen wrote: > > > On Dec 3, 2019 8:55 PM, Bill Gunshannon via cctech > wrote: > > Especially RSX180 as I have some other plans for that one. > > RSX180? Learn about something new everyday! This tidbit alone was > worth watching the thread. > Well, glad it helped. And here's more... I have succeeded in getting RSX-180 installed on a hard disk. In doing so I have learned some things that others might consider valuable as well. Disk sizes and formats are more important than one might realize from reading the support page. Oversized hard disk partitions cause really strange behavior totally unrelated to disk I/O. When I tried to use a disk partition that was too big the system merely spewed garbage to the screen. But the second lesson is even more important. The Support Page states: "For best performance format the floppy first under CP/M, so the sectors will have the optimum interleave value for the P112 hardware. Otherwise, disk accesses will be very slow." This is not accurate. When I used a brand new pre-formatted floppy without formatting it under CP/M it booted but many of the commands failed to work and even th4e directory could not be seen. Formatting on CP/M and then using rawrite to place the image on the floppy fixed that. I have been having a problem getting CP/M 3 to boot and now suspect it may be the same problem. Again, I used a pre-formatted brand new floppy and rawrite. When I try to boot it starts loading and then spews what looks like random garbage to the screen. I am going to try using a CP/M formatted floppy and I actually expect it will fix the problem. bill
Re: P112
On 12/3/19 8:15 PM, Fred Cisin via cctech wrote: > On Wed, 4 Dec 2019, Bill Gunshannon via cctech wrote: >> Along this line I have solved one problem. I mentioned INIT in >> RSX180 printing gibberish on the screen when trying to init a >> hard disk partition where it had worked on a floppy. Problem >> was the size of the partitions. I had tried just making one >> partition for the test I learned that FDISK will make partitions >> too big for any of the P112 OSes. I now have a hard disk with >> 5 partitions to play with. On to the next problem. > > Is it a specific size limit? > (something on the order of number of bits for block number?) Don't know, but I suspect it's around 32M. I seem to remember seeing something mentioned somewhere. I just divided a 42M Seagate into 5 partitions to play with. I may test the limits eventually but for right now I would just like to get some of the OSes loaded on the hard disk so I can work with them. Especially RSX180 as I have some other plans for that one. bill
Re: P112
On Wed, 4 Dec 2019, Bill Gunshannon via cctech wrote: Along this line I have solved one problem. I mentioned INIT in RSX180 printing gibberish on the screen when trying to init a hard disk partition where it had worked on a floppy. Problem was the size of the partitions. I had tried just making one partition for the test I learned that FDISK will make partitions too big for any of the P112 OSes. I now have a hard disk with 5 partitions to play with. On to the next problem. Is it a specific size limit? (something on the order of number of bits for block number?)
Re: P112
On 12/3/19 7:51 PM, Craig Ruff via cctech wrote: > Just in case someone else hasn't already responded, the P112 does not use DOS > style fdisk partitioning for a hard disk. It is done in the BIOS image, and > then the logical disks have to be initialized. This is described in the "P112 > GIDE Construction.pdf" document. > > I've only used 3.5" floppies, which work fine. You can also attach a PATA > CD-ROM drive and access disks with a program that escapes my memory at the > moment. > Along this line I have solved one problem. I mentioned INIT in RSX180 printing gibberish on the screen when trying to init a hard disk partition where it had worked on a floppy. Problem was the size of the partitions. I had tried just making one partition for the test I learned that FDISK will make partitions too big for any of the P112 OSes. I now have a hard disk with 5 partitions to play with. On to the next problem. bill
Re: P112
Just in case someone else hasn't already responded, the P112 does not use DOS style fdisk partitioning for a hard disk. It is done in the BIOS image, and then the logical disks have to be initialized. This is described in the "P112 GIDE Construction.pdf" document. I've only used 3.5" floppies, which work fine. You can also attach a PATA CD-ROM drive and access disks with a program that escapes my memory at the moment.
Re: p112
On Mon, 3 Dec 2018, Joe Smith via cctech wrote: Are there any boards available or rom monitor updates? No more boards are available. This is primarily due to difficulty in getting sufficient quantities of brand-new super-IO chips. The fabber I used has problems with using pulls because the legs are off just enough to make the pick-and-place robots throw fits. I'm pondering doing a new run of bare boards and either doing the SMT myself or leaving that for buyers. In any case, I probably won't be offering complete kits. Besides Joe, who else would be interested in acquiring one or more P112 boards? -- David Griffith d...@661.org A: Because it fouls the order in which people normally read text. Q: Why is top-posting such a bad thing? A: Top-posting. Q: What is the most annoying thing in e-mail?
Re: P112
I have a operational P112 with 3.5" floppies, GIDE/CF and CD-ROM. Do you know which ROM you have installed?
