6947ch03.fm

Draft Document for Review April 7, 2004 6:15 pm

CEC Cage

2 GB/sec

I/O Cage

 

STIs

 

 

 

STI

 

 

 

 

 

333 MB/Sec

 

I/O Cards

 

M

 

ESCON

 

STI

 

 

Book

B

1 GB/Sec

 

STI

 

A

 

 

 

 

eSTI-M

 

 

 

s

OSA-E

333 MB/Sec

 

 

 

 

ESCON

 

 

 

 

STI

 

 

 

 

 

 

 

STI

 

1 GB/Sec

 

 

 

ISC-3

 

 

 

 

500 MB/Sec

eSTI-M

OSA-E

 

12 STIs

 

 

 

 

STI

 

 

 

 

 

FICON

 

 

 

 

1 GB/Sec

 

 

 

 

 

Express

 

PCIXCC

 

 

 

 

 

 

 

 

 

STI

 

 

 

STI-2 Extender

 

500 MB/Sec

PCICA

 

 

 

 

 

 

 

 

 

ICB-2

Crypto

 

 

 

 

Cards

 

 

 

 

(333 MB/Sec)

 

 

STI-3 Extender

 

 

 

 

 

 

 

ICB-3

 

 

 

 

 

(1 GB/Sec)

 

 

 

 

 

ICB-4

 

 

 

 

 

(2 GB/Sec)

 

Figure 3-3 STIs and I/O cage connections

A Memory Bus Adapter (MBA) STI connector, located in a book, can be connected to one of the following:

￿An eSTI-M card, which creates up to four secondary STI links to connect I/O cards

￿An STI-2 Extender card, which has up to two ICB-2 links

￿An STI-3 Extender card, which has up to two ICB-3 links

￿An ICB-4 link, which attaches directly to an STI port

eSTI-M card

For each z990 I/O cage domain, the MBA-to-I/O card connectivity is achieved using an eSTI-M card and a 2 GB/sec STI cable. These half-high eSTI-M cards plug into specific slots (5, 14, 23, and 28) in the z990 I/O cage. Physical slot locations 5, 14, and 23 house two half-high eSTI-M cards, while slot 28 has only one half-high card plugged in the top.

The eSTI-M card (Feature Code 0322) takes the 2 GB/sec link from an MBA’s STI and creates four secondary STI links, which are connected to the I/O and cryptographic cards through the I/O cage board. The bandwidth of the secondary link is determined by the feature card it is attached to:

￿333 MB/sec for ESCON

￿500 MB/sec for ISC-3

￿1 Gb/sec for FICON, OSA-E, PCIXCC and PCICA

78IBM eServer zSeries 990 Technical Guide

Page 92
Image 92
IBM 990 manual ESTI-M card, Cage

990 specifications

The IBM 990 series, often referred to in the context of IBM's pioneering efforts in the realm of mainframe computing, represents a unique chapter in the history of information technology. Introduced in the late 1960s, the IBM 990 series was designed as a powerful tool for enterprise-level data processing and scientific calculations, showcasing the company's commitment to advancing computing capabilities.

One of the main features of the IBM 990 was its architecture, which was built to support a wide range of applications, from business processing to complex scientific computations. The system employed a 32-bit word length, which was advanced for its time, allowing for more flexible and efficient data handling. CPUs in the IBM 990 series supported multiple instructions per cycle, which contributed significantly to the overall efficiency and processing power of the machines.

The technology behind the IBM 990 was also notable for its use of solid-state technology. This provided a shift away from vacuum tube systems that were prevalent in earlier computing systems, enhancing the reliability and longevity of the hardware. The IBM 990 series utilized core memory, which was faster and more reliable than the magnetic drum memory systems that had been standard up to that point.

Another defining characteristic of the IBM 990 was its extensibility. Organizations could configure the machine to suit their specific needs by adding memory, storage, and peripheral devices as required. This modular approach facilitated the growth of systems alongside the technological and operational demands of the business environments they served.

In terms of software, the IBM 990 series was compatible with a variety of operating systems and programming environments, including FORTRAN and COBOL, enabling users to access a broader array of applications. This versatility was a significant advantage, making the IBM 990 an appealing choice for educational institutions, research facilities, and enterprises alike.

Moreover, the IBM 990 was engineered to support multiprocessing, which allowed multiple processes to run simultaneously, further increasing its effectiveness in tackling complex computing tasks.

In summary, the IBM 990 series represents a significant advancement in computing technology during the late 20th century. With a robust architecture, versatile configuration options, and a focus on solid-state technology, the IBM 990 facilitated substantial improvements in data processing capabilities, making it a cornerstone for many businesses and academic institutions of its time. Its impact can still be seen today in the continued evolution of mainframe computing.