SIC/XE Program to Write a subroutine to read a record into a buffer

This System Software program demonstrates a sequence of instructions in SIC/XE that will read a record into a buffer.

Write a subroutine for SIC/XE that will read a record into a buffer. The record may be any length from 1 to 100 bytes. The end of record is marked with a “null” character (ASCII code 00). The subroutine should place the length of the record read into a variable named LENGTH. Use immediate addressing and register-to-register instructions to make the process as efficient as possible.

Solution