Cell is a crossbar chipset used in HP 9000 PA-RISC Integrity servers and some Superdome mainframe computers.
The Central Electronics Complex CEC interconnects individual system and processor
cells via central crossbars.
The cell boards were seated in the backplane of the system, which provided the cell-to-cell links and I/O functionality.
The CC Cell Controller is the central chipset at the core of each cell. It connects local processors and memory on cells to the SBA I/O links and the XBC crossbar. XBC is the crossbar ASIC that provides the main backplane function, each backplane supports up two four cell modules. Different backplanes can be tied together through links through the XBCs with a high-bandwidth, low/latency connection.
M2 are the main memory controllers and converters on each cell board. There are eight M2 controllers that attach in two banks to each CC. Requests and addresses are sent directly from the CC to memory, with the data returning through the M2s.
RIO is the master I/O controller, also called SBA. The central I/O part of the main chipset, with one SBA reserved for each cell/CC, located on the (I/O) backplane. Each SBA provides sixteen 12-bit links called ropes to which slave I/O controllers connect, the LBAs. These LBAs are Elroy PCI bridges that convert the links from the SBA into PCI buses.
Core I/O is a card set that provides standard I/O functions and plugs into PCI-64 or special slots to provide third-party I/O functions. Distinct cards were availaible: MP/SCSI card and LAN/SCSI, among others.
- Two dual-channel Symbios Logic 53C1010 Ultra160 SCSI controllers
- Dual-channel Symbios Logic 53C896 Ultra2-Wide SCSI-3 controller
- Gigabit Ethernet networking
- Console, serial and management controllers
- Fast-Ethernet DEC 21142/43 for Management LAN
- Optional second Core I/O card for redundancy or partitioning
Several buses were used in Cell: Runway+ processor bus for up to four processors at 8.0 GB/s.
Memory bus to the M2, for up to two memory
banks with 4.0 GB/s peak
The SBA I/O links to the off-cell SBA have 2.0 GB/s peak,
the XBC link to the crossbar for cell-to-cell communication 8.0 GB/s peak.
- N4000 (rp7405, rp7410)
- hp server rp7410 whitepaper (URL gone)
- HP nPartition-capable Servers (URL gone)
- User Guide hp rp7405/7410 Servers (URL gone)