Most of the reference designators are covered by the component itself, thus
I had to made up many of them.
C96 Memory backup Cap?
F1 PTC fuse
F2 PTC fuse
LK2 Header for ?
OSC1 3.6864 MHz osc
OSC2 25.0000 MHz osc
SK3 DB15 ethernet (AUI)
SK4 Audio In/Out
SK8 KB/Mouse port
SK9 PS/2 Mouse
SK11 Appleprint ?
SK13 DC Power plug
SK14 40 pin VMC
SK15 Dual PCMCIA slots
SK16,17 72 pin SIMMs
SW1 Switch for?
U1 AT&T T 7213
U2 AT&T T7259 DBRI
U3 LT LTC1320CS
U4 ROS 1.21 2792
U5 Ramtron FM1608S-250SC
U6 NCR NCR89C100
U7 EPROM "W/Wort Modem"
U8 VLSI VY27004-2TS103-A
Y1 H20.000B3 xtal
Y2 H12.2960B4 xtal
Y4 35.2512 xtal
U8 is Tadpole TS103-A
SW1 is an "MW" from England, 19N502EB
Case closed microswitch.
T7259 Dual Basic Rate ISDN chip
64K bit Ferroelectric Nonvolatile RAM from ramtronics. This
is a ferroelectric technology part that acts just like RAM in the circuit,
but keeps its memory when the power is off. It provides data retention
for 10 years.
F1 PTC fuse
F2 picofuse (rework?)
U9 PPC601 FD66-1PQ
U10 VLSI VY27002-2
U11 Rockwell C2900-20
U13 Benchmarq bq2001S
U15 Crystal CS4215-KL
U16 Rockwell RC144DPL
U10 Tadpole TS102-A PCMCIA Controller
Crystal CS4215-KL spec
SK14 40 Pin SCSI Connector
This little bad boy uses a 40 pin mini-centronics connector
(like the IBM SCSI connectors). Nothing like this in PS/2 land, that's
for sure. The planar socket has a male connector.
Removable Hard Drive SCSI Connector
NCR89C100 / NCR89C105
..used the Machio/Slavio chipset for SCSI (fast-narrow, 8 bit),
Ethernet (10base-T or AUI), serial and parallel ports, controlling the
Boot PROM and NVRAM/hostid chip, and a bunch of other stuff. Part
numbers for these chips were STP2000QFP (Machio) STP2001QFP (Slavio), aka
NCR89C100 / NCR89C105. Performance is for all intents and purposes identical
on all systems using the chipset, as far as I have ever been able to tell.
SCA connectors for the SS20 was purely a physical interface issue, and
in no way utilized the 16-bit interface on the drives, as the bus and controllers
Slow I/O Subsystem
The Slow I/O subsystem is managed by an NCR89C105 SLAVIO.
SLAVIO is an application specific integrated circuit (ASIC), designed
part of a two-chip set with the NCR89C100 MACIO, which provides two
serial channels, keyboard and mouse ports, an interrupt controller
counter-timers. The key features of the SLAVIO include:
Two synchronous/asynchronous serial ports (85C30 SCC compatible)
Keyboard/mouse ports (85C30 SCC sub-set)
Two programmable counter-timers (500 ns period)
8-bit expansion bus (EBus) interface/controller for EPROM and 8-bit
Internal 82077 style floppy disk controller
Miscellaneous I/O functions.
Fast I/O Subsystem
The Fast I/O Subsystem includes the SCSI, parallel and network interfaces.
These are controlled by the NCR89C105 MACIO. This device is a custom
ASIC designed to be operated with the NCR89C100 SLAVIO as a
two-chip set. The key features of the MACIO include:
53C90 style SCSI controller (Emulex FAS100A compatible)
7990 style Ethernet controller
Parallel port interface
Dual 64 byte FIFOs
IEEE-1496 SBus DMA controller
This section describes each of these features.
The Ethernet controller provides a 10Mbit/sec networking interface.
design features an AT&T serial interface encoder to provide the
AUI interface through a 26-way high density connector. An AUI cable
an Ethernet transceiver can be used to provide access to other physical
Ethernet media, including Thick, Thin and Fiber-optic networks.
The AUI interface is DC coupled, and any attachment units used with
SPARCbook 3 must feature the network isolation function. Ethernet data
transfers are supported with the MThe Ethernet interface on the SPARCbook
is provided by an NCR92C990 integrated into the MACIO. This provides AUI
connections via a 15-pin D-shell connector. The MACIO enhances Ethernet
operations by providing DMA support.ACIO DMA function.
ISDN and 16-Bit Audio Controller
The ISDN and Audio interface consists of two major components: the
AT&T T7259 Dual Basic Rate ISDN Controller; and the Crystal
Semiconductor Corporation CS4215 Multimedia Audio CODEC.
The T7259 has the following major features:
Simultaneous terminal endpoint (TE) and network termination (NT)
CCITT I.430/ANSI T1.605 support for 4 wire ISDN 2B+D basic
access at the S/T reference point
Multiframing support: S&Q channel operation
Automatic synchronization of ISDN interfaces
On-chip HDLC formatter
On-chip 16-channel DMA address generator and linked list buffer
Supports AT&T Concentration Highway Interface (CHI)
Sbus master and slave interface
The ISDN controller combines a DMAC and data format converter
(Parallel/Serial, Serial/Parallel and Time-Division-Multiplex). It
number of DMA channels that can be allocated to support the ISDN or
audio functions. The DMACs provide linked-list command support, and
FIFOs allow burst data transfers to be performed on the Sbus. Large
amounts of ISDN or audio information can be moved to and from the Sbus
with a minimum of processor overhead. The data is formatted by the
controller into a composite digital serial stream (the Concentration
Highway Interface). This connects to additional on-chip ISDN support
circuitry, and to the external audio CODEC. The ISDN interface is
implemented as a 2B+D Terminal Endpoint.
The Concentration Highway Interface of the ISDN circuitry provides
variety of different serial digital framing standards and data rates
Audio CODEC. This supports a majority of the world standard Digital
Audio formats. Typical configurations include high-quality stereo 16-bit
44.1KHz (CD), and telephony quality mono 8-bit 8KHz (ISDN).
The CS4215 Audio CODEC has the following major features:
Stereo analog-to-digital and digital-to-analog conversion
4KHz to 48KHz sample rates
16-bit linear and 8-bit u-law or A-law coding
Serial digital interface, compatible with AT&T CHI Concentration
Microphone and line analog outputs
Baud Rate Clocks
A 19.66 MHz clock (Y5) signal generated by the MACIO is used to derive
a baud rate clock for all of the SCCs. This is divided by four before being
fed to the SCCs at 4.915 MHz. The baud rate can be changed by loading
different time constants (which can be different for each channel)
time constant register. The clocking modes 1, 2, 16, 32 and 64 are
The MACIO incorporates an enhanced NCR53C90 Fast SCSI Controller (FSC),
which supports SCSI-2 operations at up to 10 Mbytes/sec running
synchronously. SCSI transfers are supported by the MACIO's integral