HP LaserJet - Upgrading Memory of Older Models

Upgrading Memory of Older Models

Many older LaserJets and other HP printers (including LaserJet 4+, 4MV, 4MP, 4P, 5, 5M, 5MP, 5N, 5P, 5se, 5Si MOPIER, 5Si, 5Si NX, 6MP, 6P, 6Pse, 6Pxi, C3100A; DesignJet 330, 350C, 700, 750C, 750C Plus; DeskJet: 1600C, 1600CM, 1600CN; and PaintJet XL300) used proprietary 72-pin HP SIMMs for memory expansion. These are essentially industry-standard 72-bit SIMMs with non-standard Presence Detect (PD) connections. One can often adapt a standard 72-pin SIMM of appropriate capacity to support HP PD by soldering wires to pads, a simple task. HP printers of this type specify that RAM not faster than 70ns be used; this is probably due to a limitation of the PD decoding, and faster RAM can actually be used so long as the PD encoding indicates a speed of 70ns or slower. All printers will work with FPM (Fast Page Mode) memory; many, but not all, will work with EDO memory.

Even older models, such as the LaserJet II, IID, III, IIID, and 4/4M (i.e. not 4 Plus), used proprietary memory expansion boards. For example, the II and IID models used a roughly 4" square memory expansion board populated with DIP DRAM chips and a two-row header connector (with pins on standard 0.1" centers).

Read more about this topic:  HP LaserJet

Famous quotes containing the words memory, older and/or models:

    Those who believe in their truth—the only ones whose imprint is retained by the memory of men—leave the earth behind them strewn with corpses. Religions number in their ledgers more murders than the bloodiest tyrannies account for, and those whom humanity has called divine far surpass the most conscientious murderers in their thirst for slaughter.
    E.M. Cioran (b. 1911)

    The older I get, the greater power I seem to have to help the world; I am like a snowball—the further I am rolled the more I gain.
    Susan B. Anthony (1820–1906)

    Grandparents can be role models about areas that may not be significant to young children directly but that can teach them about patience and courage when we are ill, or handicapped by problems of aging. Our attitudes toward retirement, marriage, recreation, even our feelings about death and dying may make much more of an impression than we realize.
    Eda Le Shan (20th century)