Synchronous serial interface for SBus

The SSD4 is a discontinued product, and is no longer supported. This information is provided for reference only.

  • Serial rates up to 15 Mbits/sec
  • 1, 2, or 4 channels per board
  • Independent clock per channel
  • Programmable 1, 2, or 4 data bits per clock
  • RS422 compatible driver/receivers
  • SunSPARCstation compatible
  • TTL compatible driver/receivers with special cables
  • Single SBus slot
  • Device drivers for Solaris 2.4 and later
  • Monitoring serial data communications
  • Telecom receiver

The SSD4 synchronous serial interface is an SCD-20 modified to collect one to four channels of synchronous serial data. A synchronous serial interface channel is composed of one to four data bits accompanied by a clock. The data is sampled on the rising edge of the clock and stored in the host computer memory by the SCD-20 DMA. The SSD4 can be configured with one, two or four independent serial interface channels, and stores the channel number along with the data acquired from that channel.


A device driver for Solaristm is included with the SSD4. The driver provides access to the SSD4 through standard and asynchronous read and write system calls. A DMA ring buffer management library is provided for high speed continuous transfers.


Use the SSD4 with one of two optional 10 foot cables. The CAB-SS provides a differential RS-422 interface. The CAB-TTL provides a single ended TTL interface. Each cable allows up to four channels: the number of active channels and data bits in each channel depends on the configuration of the SCD-20 board and associated software.

  • Custom cables
  • Up to 100 Mbits/sec data rate available with LVDS or PECL I/O

EDT provides several levels of customer support, from phone consultation to custom design of hardware and software, at hourly rates.


SBus Compliance

Number of slots: 1
Transfer size: 1, 2, 4, 8, or 16
Words per transfer: As many as the host computer will accomodate
DVMA Master
SBus memory space: Approx. 66Kb

Data Transfer

Protocol: synchronous
Transfer: 1, 2, or 4 separate


4 channel operation- clocks up to 2.2 MHz
2 channel operation- clocks up to 5 MHz
1 channel operation- clocks up to 15 MHz


RS422 with CAB-SS
Variable with SSD4-SE chassis


Device drivers for Solaris 2.4 or later


2 A @ 5 volts


Temperature: Operating, 10° to 40° C; non-operating, -20° to 60° C
Humidity: Operating, 20% to 80% noncondensing at 40° C; non-operating, 95% noncondensing at 40° C


Single standard SBus slot
Dimensions: 3.9″ x 5.05″ x 0.5″
Weight: 3.8 oz.

Each referenced service mark, trademark, or registered trademark is proprietary to its respective manufacturer.