KROON@HGRRUG51.BITNET (Peter A. Kroon. KVI) (01/06/87)
Their is a rumour that the difference between an 18-bits and a 22-bits Q-bus backplane is just a matter of adding 4 wirewrap wires. Is this true and is there anyone out there who has succesfully performed this "upgrade"? I realize that there is probably a better bulletin topic for this problem but I don't have an overview of all the topics. If anyone could suggest a better topic for this problem to post this message please let me know (INFO-RSX? INFO-QBUS? INFO-PDP, INFO-ANTIQUE?) +----------------------KVI----------+--------------------------------------+ | Peter A. Kroon, | Phone: +31-(50)-633618 / 633600 | | Kernfysisch Versneller Instituut, | Bitnet/Earn: KROON@HGRRUG51 | | Zernikelaan 25, 9747 AA Groningen | Surfnet: KVIANA::KROON | | The Netherlands | | +-----------------------------------+--------------------------------------+
cetron%utah-ced@UTAH-CS.ARPA (Ed Cetron) (01/06/87)
this is true for most of the 'newer' old q-bus backplanes. Most of the newer newer backplanes have all the lines connected anyway.... I have done at least 6 upgrades, and know of dozens more.... One must remember however, that several old q-bus boards USE THOSE LINES FOR OTHER PURPOSES, and will cripple any true 22-bit boards.... Other boards (such as the rxv11) only do 18-bit DMA and are also hard to work with, and others (such as the bdv11) don't properly terminate the extra 4 bits..... bottom line: with some caveat's, it can be done easily.... -ed cetron center for engineering design