3770Link

IF conn_loop, connect

QUIT :connect PTR testptr SEND jcl.txt IF sendfail

RCV :sendfail

DISC

QUIT

This example LU script file dials a phone number and checks for numerous possible result codes. If the dial is successful, two files are transmitted consecutively and a RCV is executed to await the host’s reply. The line is then disconnected. This script file example also assumes that a single LU is configured for the current connection and that the INIT_SELF has been enabled and configured for the single LU specified for this connection.

:top

DIAL 1-512-555-1212

;;Check for busy signal. IFERROR= 1055 top

;;Check for no dial tone. IFERROR= 1056 no_tone

;;Other dial error occurred. IFERROR exit

;;Send two files in a row. SEND jcl.1

;;Check for any error. IFERROR exit SEND jcl.2

;;Define auto-naming printer file. PTR newdata /n

;;Wait for host reply.

RCV :exit

DISC

QUIT

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IBM 3770 manual Disc Quit

3770 specifications

The IBM 3770, introduced in the mid-1970s, was a pioneering multi-user data station known for its innovative design and functionality, aimed primarily at supporting online transaction processing. As one of the early efforts in integrating computers with communication technology, the 3770 set a foundation for subsequent advancements in the field.

One of the standout features of the IBM 3770 was its ability to support multiple user connections simultaneously. This multi-user capability allowed organizations to connect various terminals to a central computer, facilitating efficient data entry and retrieval processes. Each terminal could communicate with the mainframe, enabling users to access real-time data and execute transactions concurrently, which was revolutionary for its time.

The 3770 utilized a proprietary communication protocol that leveraged synchronous serial communication, ensuring reliable data transmission over telephone lines and enabling the automation of remote data entry. This technology reduced the need for physical interaction with centralized data processing systems, leading to increased productivity and efficiency in organizational workflows.

In terms of characteristics, the IBM 3770 was equipped with a dedicated processor for handling input and output operations. This feature offloaded routine tasks from the mainframe, optimizing overall performance and freeing up computational resources for more intensive processing activities. Additionally, the system was designed to support a variety of input devices, including keyboards and card readers, accommodating different user preferences and operational needs.

The architecture of the IBM 3770 included a unique data format that streamlined the handling of transactions. This format allowed for easy integration with existing databases and applications, making it an attractive solution for businesses looking to modernize their data processing capabilities. The system also featured built-in error detection and correction routines, which ensured data integrity during transmission.

Moreover, the IBM 3770 was recognized for its flexibility and scalability. Organizations could easily expand their networks by adding more terminals or connecting additional mainframe storage. This scalability was crucial for businesses experiencing growth, as it eliminated the need for frequent system overhauls.

In summary, the IBM 3770 was more than just a data station; it was a significant step forward in online transaction processing, combining innovative communication technologies with multi-user functionality. Its features, such as dedicated processing, support for various input devices, and scalability, set the stage for future advancements in data systems and remain influential in shaping the landscape of computing.