Bar Chart Plotting Subroutine

This document contains the documentation and source code for a bar chart plotting subroutine, written in MACRO-8 for a Digital Equipment Corporation (DEC) computer system. The program was originally developed at Texas Instruments Limited in Bedford, England, as part of a power transistor test system.

The subroutine allows users to generate bar charts on a teletype (TTY) by reading data from an existing table without altering the original data. It provides the flexibility to create a variety of charts from the same dataset by adjusting the following seven parameters:

1. The octal address of the source table.
2. The total number of readings to be processed.
3. The table increment (reading interval).
4. The number of distribution classes.
5. The Y-axis increment value (horizontal scale).
6. The lower limit of the data range.
7. The upper limit of the data range.

The program includes necessary utility subroutines for integer division, decimal printing, and constant configuration. The document also provides illustrative examples showing how different class ranges and axis values affect the resulting output, followed by the complete assembly code listing for the subroutines.