seven@nuchat.UUCP (David Paulsen) (12/11/87)
I've got a 1700 RAM expansion, intended for the Commodore 128. After goofing around with it for a few months, I've accumulated some questions I'm having trouble getting answers for: 1. Where can I obtain a disk emulator for the thing, so that I can SAVE and LOAD files to/from RAM just like DOS? I had the impression that a utility like that would come on the disk; it's really the reason I got it in the first place. 2. I've heard that a 128K 1700 expansion cartridge can be upgraded to a 512K 1750 cartridge... true? Difficult to do? 3. What chip is supposed to go in the "U18" location on the circuit board? (Yes, I've already taken it apart! Bye-bye warranty...) 4. Can more than one 1700/1750 be utilized at the same time, via a motherboard? What does this do to the 128's power supply? 5. What's the difference between the 1700/1750 and the 1764, aside from the new power supply? I have already upgraded my old 64's p.s. to a huge mutha 9A regulated bench supply... does this mean I can just plug 'er in to the 64 without frying anything? 6. With the 1700 installed on a 128, I GO 64. From 64 mode, the MMU doesn't let me see any of the 128's memory beyond 1 64K page... can the REC, in the 1700, even in 64-mode, see the whole 128 memory map? As far as "friendly" Ramdisk emulators, the kind that allow OPEN as well as DLOAD and DSAVE, I've been working on one myself. It utilizes the REC's swap capabilities to switch out chunks of the 128's RAM so it appears to the o/s that there's very little overhead to the ramdisk software. My actual overhead is a little over 300 bytes, allowing about 11K of "actual" ramdisk support software to be swapped in as needed. It even works with most interrupt-driven utilities, as long as they put the vector back where they found it, or pass it thru... other than that, it's totally transparent. Anyone doing anything with their 1700/1750's? -- David Paulsen ...uunet.UU.NET!nuchat!seven "Commodore VIC-20... the wonder computer of the 80's!"
hedley@cbmvax.UUCP (Hedley Davis) (12/15/87)
In article <465@nuchat.UUCP> seven@nuchat.UUCP (David Paulsen) writes: > > >I've got a 1700 RAM expansion, intended for the Commodore 128. After goofing >around with it for a few months, I've accumulated some questions I'm having >trouble getting answers for: > >1. Where can I obtain a disk emulator for the thing, so that I can SAVE and >LOAD files to/from RAM just like DOS? I had the impression that a utility like >that would come on the disk; it's really the reason I got it in the first >place. > The RAMDOS is now shipping with the 1700/1750/1764's. It has been for sometime now ( a few months ). Suggest you find a user group, or a dealer with the disk, and copy it. The binary is in the public domain. >2. I've heard that a 128K 1700 expansion cartridge can be upgraded to a 512K >1750 cartridge... true? Difficult to do? Yes, this is easy ( if the rams are not soldered in ). All you need to cut open J1, and replace all the rams with 41256-15 types. > >3. What chip is supposed to go in the "U18" location on the circuit board? >(Yes, I've already taken it apart! Bye-bye warranty...) That is for a rom. We are not shipping the unit with a rom. > >4. Can more than one 1700/1750 be utilized at the same time, via a motherboard? >What does this do to the 128's power supply? > It is our official policy that only one thing can be inserted in the cartridge slot at any time. Lots of people do not listen to us. :-) As for 1700/1750/1764s, this would be a really bad idea. The power supplied with the system is NOT sufficient to power two ram expansions. > >5. What's the difference between the 1700/1750 and the 1764, aside from the >new power supply? I have already upgraded my old 64's p.s. to a huge mutha >9A regulated bench supply... does this mean I can just plug 'er in to the 64 >without frying anything? > They are essentially identical. There is a single resistor which must be removed for use with a 64. This is R4. On a C64 R4 must be removed. On a C128, R4 must be installed. Understand that we cannot condone your power supply with our equipment. It sounds ok, but we warrent nothing with regard to that usage of your equipment. > >6. With the 1700 installed on a 128, I GO 64. From 64 mode, the MMU doesn't >let me see any of the 128's memory beyond 1 64K page... can the REC, in the >1700, even in 64-mode, see the whole 128 memory map? > No. >As far as "friendly" Ramdisk emulators, the kind that allow OPEN as well as >DLOAD and DSAVE, I've been working on one myself. It utilizes the REC's swap >capabilities to switch out chunks of the 128's RAM so it appears to the o/s >that there's very little overhead to the ramdisk software. My actual overhead >is a little over 300 bytes, allowing about 11K of "actual" ramdisk support >software to be swapped in as needed. It even works with most interrupt-driven >utilities, as long as they put the vector back where they found it, or pass >it thru... other than that, it's totally transparent. > This is how ours works, although the stats are slightly different. We use a single page for the "link" and swap about 8k of code. Our code should be transparent in the same way yours is. ( Betcha its better :-) ). >Anyone doing anything with their 1700/1750's? They seem to sell well, so people are using them for something. > >-- >David Paulsen ...uunet.UU.NET!nuchat!seven > >"Commodore VIC-20... the wonder computer of the 80's!" Hedley Davis
seven@nuchat.UUCP (David Paulsen) (12/23/87)
In article <2943@cbmvax.UUCP>, hedley@cbmvax.UUCP (Hedley Davis) writes: > In article <465@nuchat.UUCP> seven@nuchat.UUCP (David Paulsen) writes: >> >>I've got a 1700 RAM expansion, intended for the Commodore 128. >> >>1. Where can I obtain a disk emulator for the thing, so that I can SAVE and >>LOAD files to/from RAM just like DOS? I had the impression that a utility like >>that would come on the disk; it's really the reason I got it in the first >>place. >> > > The RAMDOS is now shipping with the 1700/1750/1764's. It has been for > sometime now ( a few months ). Suggest you find a user group, or a > dealer with the disk, and copy it. The binary is in the public domain. > That's what I was hoping you'd say. Unfortunately, the user groups I've contacted didn't have it, and I can't locate any knowledgeable dealers in the Houston area. Granted, I only recently moved here, but the dealers I've visited looked at me funny when I explained what I was after. What's the chances of getting a copy from Commodore themselves, or failing that, the address/phone of a dealer SOMEPLACE who knows what a 1700 Ram expansion is? Is there anyone out there in netland with Q-Link access who already has this program? I'd be willing to send you a disk, return postage paid, or even reimburse the download charges... I've really got to have that ramdisk emulator. Thanks in advance! -- David Paulsen - CHARTER MEMBER, WILLIAM WINDOM FAN CLUB ..uunet!nuchat!seven "It had a maw that could swallow a DOZEN starships!" --Commodore Matt Decker, chewing on the scenery again
bs@pbhye.UUCP (Bruce J. Skelly) (12/29/87)
In article <2943@cbmvax.UUCP>, hedley@cbmvax.UUCP (Hedley Davis) writes: > > The RAMDOS is now shipping with the 1700/1750/1764's. It has been for > sometime now ( a few months ). Suggest you find a user group, or a > dealer with the disk, and copy it. The binary is in the public domain. -----------------------------------------^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ If the binary is in the public domain, could some one that has it please uuencode it and post it to the net. Thanks -- Bruce Skelly