===== EB66+ ===== ^ EB66+ ^^ ^ CPU | [[wp>Alpha_21064#Alpha_21066A|21066A]] (LCA45), up to 233 MHz | ^ Core logic | Integrated in CPU | ^ Memory | 6 SIMM slots, ECC DRAM, up to 384 MiB | ^ Buses | 32-bit PCI, ISA | ^ Form factor | Baby AT | ^ Onboard I/O | IDE, floppy, 2 serial, parallel, keyboard, mouse | ^ Firmware | SRM, MILO | ^ Kernel option | ''CONFIG_ALPHA_EB66P'' | ^ Linux | Linux 6.9 and earlier | The Alpha 21066A Microprocessor Evaluation Board (EB66+) is a baby AT form factor evaluation and development board for systems based on the Alpha 21066A microprocessor. ==== Specifications ==== * 21066A CPU running at up to 233 MHz; lower frequencies are available through onboard jumpers [(>{{wiki:hardware:motherboards:eb66plus:eb66plus_user_guide.pdf?linkonly|Alpha 21066A Microprocessor Evaluation Board (EB66+) User's Guide}})] * 1 MiB external backup cache (Bcache), can emulate 256 KiB or 512 KiB by jumper * 6x 72-pin 36-bit SIMMs in three banks of identical pairs, supports 8 MiB to 384 MiB of ECC DRAM (70 ns or faster) * PCI bus integrated into the 21066A, running at 33 MHz * 4x PCI slots (one shared with ISA) * 5x ISA slots (one shared with PCI) * Intel 82378ZB PCI-to-ISA bridge * National PC87312 combination controller: IDE, diskette, 2x serial ports, parallel port (all on onboard headers) * Intel 8242 keyboard and mouse controller * Dallas Semiconductor DS1287 time-of-year clock * Serial ROM and flash ROM containing a debug monitor * Baby AT board, 33.02 cm x 22.1 cm (13.0 in x 8.7 in) [(>{{wiki:hardware:motherboards:eb66plus:eb66plus_user_guide.pdf?linkonly|Alpha 21066A Microprocessor Evaluation Board (EB66+) User's Guide}}, pp. 1-4, 3-28)] ==== Firmware ==== DEC distributed SRM consoles for the EB66 and EB66+, along with its other evaluation boards, as part of its evaluation board software development kit. [(>[[https://github.com/alphalinux/mailing-list-archives/blob/main/axp-list-mbox/1998-January.mbox#L3642|"Re: SRM license issues"]], Jay Estabrook, axp-list, 6 Jan 1998)] ==== Linux ==== Linux 6.9 was the last version to support the EB66+; Linux 6.10 removed support for processors older than the EV56 (21164A). [(>[[https://git.kernel.org/torvalds/c/a4184174be36|"alpha: drop pre-EV56 support"]], Linux 6.10)] Kernels up to 6.9 support it with ''CONFIG_ALPHA_EB66P'' or a generic kernel. [(>[[https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/alpha/Kconfig?h=v6.9|arch/alpha/Kconfig]], Linux 6.9)] The MILO image is named ''eb66p''. [(>[[https://github.com/alphalinux/mailing-list-archives/blob/main/axp-list-mbox/1998-March.mbox#L30004|"Re: AlphaServer 800"]], Jay Estabrook, axp-list, 25 Mar 1998)] [(>[[https://github.com/alphalinux/mailing-list-archives/blob/main/axp-list-mbox/2004-September.mbox#L5923|"Alpha Core ISO Images"]], Jay Estabrook, axp-list, 29 Sep 2004)] The board uses the same interrupt design as the [[hardware:motherboards:pc64|AlphaPC 64]] (Cabriolet). [(>[[https://github.com/alphalinux/mailing-list-archives/blob/main/debian-alpha-mbox/2000-February.mbox#L6964|"Re: Weird Lockups II"]], Richard Henderson, debian-alpha, 20 Feb 2000)] For the original EB66, see [[hardware:motherboards:eb66|EB66]]. In kernels up to 6.9, the onboard devices use these drivers: * IDE (PC87312): the interface is not a PCI device, so it is handled by ''pata_legacy'', which probes the legacy ports at 0x1F0 and 0x170 when no PCI controller claims them. [(>[[https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/ata/pata_legacy.c?h=v6.9|drivers/ata/pata_legacy.c]], Linux 6.9)] No Linux driver was written to use more than PIO modes on the PC87312. [(>[[https://github.com/alphalinux/mailing-list-archives/blob/main/axp-list-mbox/2000-January.mbox#L27608|"Re: EB164 onboard IDE characteristics"]], Jay Estabrook, axp-list, 19 Jan 2000)] * Serial ports: ''8250'', at the standard PC addresses listed in the Alpha serial port table. [(>[[https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/alpha/include/asm/serial.h?h=v6.9|arch/alpha/include/asm/serial.h]], Linux 6.9)] * Parallel port: ''parport_pc''; floppy: ''floppy''; keyboard and mouse: ''i8042''. [(>[[https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/parport/parport_pc.c?h=v6.9|drivers/parport/parport_pc.c]], Linux 6.9)] [(>[[https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/block/floppy.c?h=v6.9|drivers/block/floppy.c]], Linux 6.9)] [(>[[https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/input/serio/i8042.c?h=v6.9|drivers/input/serio/i8042.c]], Linux 6.9)] ==== Known issues ==== * **Clock battery:** the Dallas DS1287 time-of-year clock contains a sealed lithium cell that keeps the clock and its RAM running without power, [(>{{wiki:hardware:motherboards:eb66plus:eb66plus_user_guide.pdf?linkonly|Alpha 21066A Microprocessor Evaluation Board (EB66+) User's Guide}}, pp. 1-6, 3-16)] so the chip itself must be replaced once the cell is exhausted. For a replacement part, see [[hardware:motherboards:axppci33#known_issues|AXPpci 33: Known issues]]. See also [[hardware:systems#common_problems|Systems: Common problems]]. ==== Documentation ==== ^ Document ^ Part number ^ Date ^ | {{wiki:hardware:motherboards:eb66plus:eb66plus_user_guide.pdf?linkonly|Alpha 21066A Microprocessor Evaluation Board (EB66+) User's Guide}} | EC-QDVCB-TE | February 1995 | {{tag>hardware motherboard 21066 digital}}