[HECnet] Bringing up a MicroVAX 3100-80

On 3/30/2020 8:44 PM, Supratim Sanyal wrote: to boot dka400, didn't work. The internet is flush with discussions about "special format" CD-ROM, ODS vs ISO, 2048 byte vs 512 byte blocks, etc. disk image"). So basically I have to research and find a way to burn a CD-ROM in the necessary format that will boot the MicroVAX into DCL so that I can repair the CONTIGUOUS issue on DKA100. am trolling the internet. The file downloaded from HPE for OpenVMS V7.3 is a Backup saveset and can't be written directly to a CD to create a bootable disk. My disk image I got from an actual OpenVMS VAX V7.3 CD. Assuming you have a disk image you can use then you can follow this. It's very simple on the Mac 1) Navigate in Finder to the CD image file 2) Right click on the file, should bring up a menu list and you choose 'Burn "xxxxxxx" to Disc...' 3) In the dialog choose the slowest burn speed. I don't have any proof, but I've always gotten better result with slower speeds. I typically chose the 4x speed. 4) Choose "Verify" just for safety. I also choose "Eject on finish" since the Mac can't mount the OpenVMS CD file system anyway. 5) Start the CD burn The CD-R that I use are 700MB 80 minute ones. The brand is Philips. Not sure how much difference that makes. It's been along time since I did any testing. I have a large supply of the current ones so I haven't needed to shop in a few years. Unless there is corruption in the disk image you use, that should be all you have to do. Windows people have a little more, they usually need a special program but the Mac's CD burn program works just fine for OpenVMS images. When writing the CD, you don't need to worry about the 512 vs 2048 byte block problem. That's only for the CD drive hooked to the VAX. An RRD42 has the appropriate block size. The only thing I don't know is if an RRD42 is too early of a drive to handle a CD-R or not. My oldest DEC drive is an RRD43 in my InfoTower. My MicroVAX 3100 has a Toshiba XM-5701A which is a RRD45 or RRD46 equivalent. My InfoTower is not set up at the moment but the MicroVAX can read the burnt disk without problem. So I just wrote a V7.3 CD from image and it worked okay. I downloaded the V5.5-H4 image from VAXHaven and I get an "unrecognizable format" message from the Mac when selecting the "AG-PXL1A-RE.iso" to burn. I examined it in DiskImageMounter but it can't figure out the format either. It's possible the image is corrupted on the VAXHaven site. It's also possible that DEC used an internal format on the CD that the current software doesn't know about. Some combination of ISO and Joliet, perhaps. So next I downloaded the OpenVMS VAX V6.1 image from VAXHaven (AG-PXKUC-RE.ISO) and it burned okay. I can mount it in my MicroVAX and read the save sets off of it. II have another copy of V5.5-2H4 that I got from www.winworldpc.com at the hint of one of these message boards. Maybe Classic Comp. But it gives the same "Could not burn "VMS 552h4 VAX.iso". The disk image is invalid." error so I'm betting it's probably a copy of the VAXHaven image. I got a V5.5-2 from there and I can burn that. More and more I think the VAXHaven V5.5-2H4 image may be corrupted. -- John H. Reinhardt