slif@oliveb.UUCP (Mike Slifcak) (07/25/87)
Hello ! Pardon my ignorance. I want to know if PC Jr.'s can read and write MS-DOS 5.25" floppies. Also, can PC Jr.'s work with programs expecting Color Graphic Adapter. Finally, what is a typical memory config, and the maximum expansion. What other incompatibilities to PC XT that you know about. Thanks for your help. Mike Slifcak
byrnes@ge-dab.GE.COM (Arthur J. Byrnes) (07/26/87)
> > Pardon my ignorance. > I want to know if PC Jr.'s can read and write MS-DOS 5.25" floppies. > Also, can PC Jr.'s work with programs expecting Color Graphic Adapter. The PCJr writes IBM standard double sided 360k floppies. The graphics adapter is fully compatable with the CGA card on an xt/pc. Be sure to use the bios interface when programming, (this is great aadvice to any programming done for the IBM and clones.) The "standard" configuration for the jr is 128k memory. It can be expanded to the full dos limit, 640k, but only using special add ons which may or may not still be available. > What other incompatibilities to PC XT that you know about. The XT has very poor sound when compaired to the Jr. But if the programmer has done his job properly, and not tried to prove how well he can avoid the bios 1/3 :-), any program should run on either machine. > Thanks for your help. You're Welcome. Arthur J. Byrnes UUCP: ...!mcnc!ge-rtp!ge-dab!byrnes General Electric GEnet: advax::byrnes 1800 Volusia Ave, Rm 4412 Voice: +1 904 258 2507 Daytona Beach, FL 32015 Disclaimer; These views are those only of the author, Arthur.
tim@ur-cvsvax.UUCP (Tim Takahashi) (07/26/87)
In article <2275@oliveb.UUCP>, slif@oliveb.UUCP (Mike Slifcak) writes: > > I want to know if PC Jr.'s can read and write MS-DOS 5.25" floppies. > Also, can PC Jr.'s work with programs expecting Color Graphic Adapter. Yes, the PC Jr when equipped with a disk drive, reads and writes diskettes in the standard :-) IBM PC 360k MSDOS disk format. (Realize that the Jr. isn't exactly a high priority device for hardware developers - so don't hold your breath for much new stuff) However, there is a firm that advertises in PC magazine that sells a second disk drive, memory exapansion and DMA chip for a Pc Jr. As far as the CGA is concerned. I have a Tandy 1000SX that comes with a PcJr graphics board emulator (standard equipment). Most anything will run with the Pc Jr graphics. (You simply have more colors to choose from). Tim Takahashi
omega@ut-ngp.UUCP (Omega.Mosley`) (08/11/87)
In article <661@ge-dab.GE.COM>, byrnes@ge-dab.GE.COM (Arthur J. Byrnes) writes: > > > > Pardon my ignorance. > > I want to know if PC Jr.'s can read and write MS-DOS 5.25" floppies. > > Also, can PC Jr.'s work with programs expecting Color Graphic Adapter. > The PCJr writes IBM standard double sided 360k floppies. ...it also writes single-sided as well, but I'm not sure about the 1.44 meg format. Also, unless IBM has solved the problem, the Jr will not format 3 1/2" disks under any circumstances despite the fact it will read the blasted things. there was once a twin-drive undercarrage available for the Jr, but reportedly never sold because of the DOS problem. This was too bad, since the unit only cost 199 bucks (99 when it was phased out last May) for two drives and the controller (it replaced the 5 1/2 one, tho...) > The graphics adapter is fully compatable with the CGA card on an xt/pc. > Be sure to use the bios interface when programming, (this is great aadvice > to any programming done for the IBM and clones.) ...this is true, however many software developers are now ignoring some of the BIOS calls that prodice different results when used in the Jr rather than an XT. This takes any redefined ASCII graphics and retranslates them back into the original form. Two games, Space QUest and Pinball Construction Set, are notorious for this problem, and thier developers really have no interest in helping the Jr user in fixing the problem. > The "standard" configuration for the jr is 128k memory. It can be > expanded to the full dos limit, 640k, but only using special add ons > which may or may not still be available. ...actually, to boost your Jr to 640k, all you need is a sidecar (IBM's or Techmar's. This will not work on Microsoft's Mousecar), 18 256k chips, a jumper wire, a pair of dykes (nonono...Diagonal Cutters, you twit!), Soldering (pronounced SOL-DER-IN') Gun, Solder, Vaccuum pump, and a LOT of patience. Once you get these, if I can figure out how I'll post up a doc file on how to install teh new chips. You will also need a file called PCJRMEM.COM, which is installed mby CONFIG.SYS, and will only work with DOS 2.1. This may pose a problem, but how many Jr. owners have a hard drive? > > What other incompatibilities to PC XT that you know about. > The XT has very poor sound when compaired to the Jr. > But if the programmer has done his job properly, and not tried to > prove how well he can avoid the bios 1/3 :-), any program should Omega.Mosley ...who owns a Jr and is damn proud of it!
brucer@gvgpsa.UUCP (Mitch Hendrickson) (08/12/87)
In article <5862@ut-ngp.UUCP> omega@ut-ngp.UUCP (Omega.Mosley`) writes: >format. Also, unless IBM has solved the problem, the Jr will not format 3 1/2" >disks under any circumstances despite the fact it will read the blasted things. Well, just 2 weeks ago I made mine format a 3.5" disk. I'm using an add-on from ES Quality Products (it plugs into the proc socket for 640k + extra drive + clock) and DOS 3.2's DRIVER.SYS. I've bagged ES' twoddisk.sys software (all it did was increment the config word and reboot) and all's well. >...actually, to boost your Jr to 640k, all you need is a sidecar (IBM's or > . > . > . ...or the above mentioned board. No connection, just a very satisfied customer. -mitch (...tektronix!gvgpsa!brucer)
km@emory.uucp (Ken Mandelberg) (12/16/87)
I just got some surplus PC Jr hardware at a surplus sale, and wonder if someone can give me some help. 1) I got an IBM 128K memory expansion module. It came with just the module and instruction booklet but no diskette. The hardware checks out ok, the powerup diagnostics see the memory and test it properly. However, I guess I need the installation diskette to make DOS know its there. Would some kind soul be willing to copy their installation diskette for me? It strikes me that there is no real license issue here since IBM bundles the diskette with each module sold. 2) I also got a power expansion module. This came with no documentation at all, just the module. The board has a 3 prong connector on one side that looks like it is for a power cord. -- What plugs into the 3 prong connector. Is there an external power supply I just didn't get? -- Under what conditions is the power expansion module needed? So far I have 128K, one floppy, and the modem all internal with one sidecar 128K expansion module, and one sidecar parallel port. It seems to work without the power expansion module. -- Ken Mandelberg | {decvax,sun!sunatl,gatech}!emory!km UUCP Emory University | km@emory BITNET Dept of Math and CS | km@emory.ARPA ARPA,CSNET Atlanta, GA 30322 | Phone: (404) 727-7963