System Chassis for QBus Systems =============================== BA11-M 2U high 19" rackmount box PDP-11/03 type chassis H9270 18-bit 4 x 4 backplane, serpentine H780 PSU (5V @ 18A, 12V @ 3.5A) adjustable BA11-N 3U high 19" rackmount box PDP-11/03L or PDP-11/23 type chassis H9273 18-bit 4 x 9 backplane, straight H786 PSU (5V @ 22A, 12V @ 11A) adjustable, min.load 2A@5V BA11-S 3U high 19" rackmount box (airflow left to right) PDP-11/23-plus type chassis H9276 22-bit 4 x 9 backplane, straight W1 inserted enables LTC signal; W2/3 not used rear fan is 70cfm H7861 PSU (5V @ 2-36A, 12V @ 5A) adjustable, min.load 2A@5V front fan is 100cfm Bezel assembly jumpers: W1,W2: in = AUX ON enables LTC out = AUX can control power controller via cable to J2 W3: out for main box, in on expander box (HALT switch -> RUN LED) W4: in for main box (SRUNL controls RUN LED) BA11-V small form tabletop box (airflow left to right) for OEM/experimental users includes PSU, 2 x 2 18-bit backplane, sepentine (similar H9281-BA) PSU does not generate LTC signal BA23-A 3U high 19" box microPDP-11 type chassis may be rackmounted (BA23-AR) (airflow left to right) commonly floor-standing, cased (BA23-AF), "storage heater" (airflow bottom to top) metal chassis slides out back, drives slide out front or desktop (airflow left to right) H9278-A 22-bit 4 x 8 backplane expandable to BA23-C box top 3 slots straight, rest serpentine; pluggable termination H7864 PSU (230W 5V @ 4.5-36A, 12V @ 6A) (Rev.12 30-20444-00) or H7864-A PSU (230W 5V @ 4.5-36A, 12V @ 7A) (Rev.20 30-21749-00) NB 230W => cannot use both rails at max current simultaneously 10V/12V fan output not included in the 230W spec 12V supply has 9-12A overload capacity for drive startup voltages NOT adjustable test points for +5/+12V on front panel SW1 (one of the small DIL switches) on operators panel disables LTC space for two mass-storage devices on sleds only one should be a hard disk (power consideration) BA123-A "World Box" microPDP-11 type chassis floor-standing on casters, "hostess trolley" (airflow top to bottom) not rack-mountable (no H-number) 22-bit 4 x 13 backplane (assembly 54-17507-01) (backplane part no. 70-22019-00) *not* expandable top 4 slots straight, 5-12 serpentine, 13 is power-only slot 13 for M9058 signal distribution card in C+D (A+B empty) fixed termination packs between slots 12 and 13 two PSU regulators (each 230W 5V @ 4.5-36A, 12V @ 7A) NB 230W => cannot draw max current from both rails simultaneously regulator A supplies odd-numbered slots and storage shelves 3,4,5 regulator B supplies even-numbered slots and storage shelves 1,2 CAUTION early power harnesses had an overheating problem see FCO BA123-I001 (ECO 70-22380-MK004 January 1988) old cable: 17-00865-01; new cable: 17-01311-02 (white connectors) fans are dual-speed controlled by sensor at right rear of cabinet second sensor shuts down PSU if too hot card-cage door sensor switches fans to high speed front panel DIL switches control LTC and Run/Restart inhibit mass-storage shelves are numbered 1 (bottom) to 4 (top) and 5 (LHS) panel/cover removal: RHS: open rear door and loosen captive screw at lower right (rear) pull bottom of panel (has 2 snap fasteners) outwards unhook panel from lip on top of frame LHS: loosen captive screw at lower right (front) pull bottom of panel (has 2 snap fasteners) outwards unhook panel from lip on top of frame H909 3U general-purpose enclosure similar appearance to PDP-11/34 or PDP-8/A box includes fan, bezel, but not backplane or PSU intended for OEM use with DDV-11E backplane and H780 PSU or similar QBus backplanes =============== DDV11-B 18-bit 6 x 9 backplane, serpentine connectors A+B, C+D are QBus connectors E+F have only +5V, GND, and -12V (*not* +12V) optional card cage, H0341 (included in H909 chassis) has screw terminals for standard power has 2x5 Berg pins for PSU signal (eg from H780, H786 etc) H9270 18-bit 4 x 4 backplane, serpentine, with card guides no bus termination mainly in BA11-M expansion boxes, can be mounted directly to H780 H9270-Q 22-bit version of H9270 H9273-A 18-bit 4 x 9 backplane, straight, with card guides no bus termination normally used in BA11-N W1 enables LTC signal when inserted (remove in expansion boxes) W2,W3 inserted only if quad-height LSI-11 M7264 in slot 1. H9275-A 22-bit 4 x 9 backplane, serpentine, with card guides 120-ohm bus termination OEM use, designed to fit BA11-N W2-5 connect upper 4 address bit to slot 1 A+B W6-9 connect upper 4 address bit to slot 1 C+D install all for 11/23 remove W2-5 install W6-9 for LSI-11/2 remove W6-9 for LSI-11 (W2-5 "don't care") H9276 22-bit 4 x 9 backplane, straight, with card guides 120-ohm bus termination designed for BA11-S H9278-A 22-bit 4 x 8 backplane, mixed, with card guides slots 1-3 straight (A+B are Qbus, C+D are CD Interconnect) slots 4-8 are serpentine optional 120-ohm bus termination (pluggable resistor packs) designed for BA23 H9281-AA 18-bit 2 x 2 backplane, without card guides H9281-AB 18-bit 2 x 4 backplane, without card guides H9281-AC 18-bit 2 x 6 backplane, without card guides H9281-AA 18-bit 2 x 2 backplane, with card guides H9281-AB 18-bit 2 x 4 backplane, with card guides H9281-AC 18-bit 2 x 6 backplane, with card guides dual-height modules only 2 x 4 and 2 x 6 versions include bus termination normally OEM use has screw terminals for standard power has 2x5 Berg pins for PSU signal (eg from H780, H786 etc) Bus and backplane notes ======================= Some backplanes have additional features. For example, some with CD Interconnect have jumpers which can be removed to disconnect MSPAREA (pin AK1) from MSPAREB (pin AL1) and MSPAREA (pin BK1) from MSPAREB (pin BL1) on the top slot. Some backplanes have SRUN L (pin AH1) on slots other than slot 1, to accomodate use of the CPU in other than the top slot. Some quad-height devices can be used in either straight or serpentine backplanes; others cannot. In some cases, it will be necessary to alter device jumpers to provide (or remove) continuity for bus grants (BIAK L on pins CM2 and CN2, and BDMG L on pins CR2 and CS2). A 22-bit CPU in an 18-bit backplane behaves as an 18-bit system. The upper address bits (which are active-low on a QBus) will simply appear to be zeros. This will not affect I/O page access, as it's controlled by a separate signal (BBS7 L). However, on some CPUs, ODT will still behave as if it's 22-bit. It is possible to convert an 18-bit backplane to 22-bit operation by bussing the extra 4 address lines: connect BC1, BD1, BE1, and BF1 on each slot, to the next. If it's a serpentine backplane, similarly connect DC1, DD1, DE1, DF1. Serpentine backplanes have the following slot order: slot 1 A+B ----------> slot 1 C+D (position 1) (position 2) | V slot 2 A+B <---------- slot 2 C+D (position 4) (position 3) | V slot 3 A+B ----------> slot 3 C+D (position 5) (position 6) | V slot 4 A+B <---------- slot 4 C+D (position 8) (position 7) | :