7.2 Understanding SCSI

SCSI (pronounced .scuzzy.) stands for Small Computer Systems Inter- face. SCSI is an industry standard computer interface for connecting SCSI devices to a common SCSI bus.

A SCSI bus is an electrical pathway that consists of a SCSI interface installed in a computer and one or more SCSI devices. SCSI cables are used to connect the devices to the SCSI interface. For the SCSI bus to function properly, a unique SCSI ID must be assigned to the SCSI inter- face and each SCSI device connected to it, and the SCSI bus must be properly terminated.

7.3 SCSI IDs

Each device attached to the SCSI bus, as well as the SCSI controller itself, must be assigned a unique SCSI ID number from 0 to 15. A SCSI ID uniquely identifies each SCSI device on the SCSI bus and determines priority when two or more devices are trying to use the SCSI bus at the same time.

Refer o the device.s documentation to set the SCSI ID. Here are some general guidelines for SCSI IDs:

For internal SCSI devices, the SCSI ID usually is set by configuring a jumper on the device.

For external SCSI devices, the SCSI ID usually is set with a switch on the back of the device.

SCSI ID numbers don.t have to sequential, as long as the SCSI control- ler and each device has a different number.

For example, you can have an internal SCSI device with ID 0, and an external SCSI device with ID 6.

SCSI ID 7 has the highest priority on the SCSI bus. The priority of the remaining IDs, in descending order, is 6 to 0, then 15 to 8.

The on-boards SCSI interface is preset to SCSI ID 7 and should not be changed. This gives it the highest priority on the SCSI bus.

Most internal SCSI hard disk drives come from the factory pre-set to SCSI ID 0.

If you have 8-bit (or Narrow) SCSI devices, they must use SCSI IDs 0, 1, 2, 3, 4, 5, or 6. SCSI ID 0 is recommended for the first SCSI hard disk drive.

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Advantech PCA-6187 user manual Understanding Scsi, Scsi IDs

PCA-6187 specifications

The Advantech PCA-6187 is a high-performance industrial PC/104-Plus single-board computer designed to meet the rigorous demands of embedded applications. This robust and versatile board is particularly well-suited for applications in industrial automation, transportation, and telecommunications, where reliability and performance are paramount.

One of the main features of the PCA-6187 is its support for the Intel Pentium M and Celeron M processors, providing a potent combination of processing power and energy efficiency. This architecture allows for the execution of complex computation tasks while maintaining a low thermal profile, making it ideal for environments with limited cooling options. Furthermore, the PCA-6187 offers a wide operating temperature range, from -40°C to +85°C, ensuring reliable functionality in extreme conditions.

The board incorporates advanced memory capabilities, supporting up to 1GB of SDRAM with a 64-bit data bus. A flash disk interface is also available for high-speed storage solutions, making it easier to manage large amounts of data typical in industrial applications. Additionally, the PCA-6187 features several I/O options, including multiple COM ports, USB interfaces, and parallel ports, allowing for extensive connectivity options for various peripherals and devices.

One of the standout characteristics of the PCA-6187 is its PC/104-Plus form factor, which allows for a modular architecture. This design enables developers to easily expand the capabilities of the board by stacking additional PC/104 modules, facilitating the customization of hardware solutions tailored to specific application requirements. The PCA-6187 also includes watchdog timers to ensure system reliability and prevent system lock-ups, which is critical for mission-critical applications.

Furthermore, the PCA-6187 supports various operating systems, including Windows and Linux, providing developers with flexibility in software development. The integration of rich development resources and tools enhances the speed and efficiency of application deployment in diverse environments.

In conclusion, the Advantech PCA-6187 stands out as a powerful and flexible industrial single-board computer, perfectly suited for a wide array of embedded computing tasks. With its robust design, advanced processing capabilities, and extensive connectivity options, it provides an ideal platform for developers aiming to create reliable systems in demanding operational conditions. The PCA-6187 truly embodies the essence of industrial computing, balancing power and efficiency for a wide range of applications.