80-Bus News


May–June 1984, Volume 3, Issue 3

Page 7 of 51

A minor criticism of PEN as far as I am concerned is that after formatting the cursor always moves to the start of the text. I would have preferred it to display from the position at which the format command was given. This is usually what I want to see after formatting so I have to step through the text until I find the required position again, which is a little annoying, although use of ‘*’ and ‘=’ commands (which are cursor position markers) would probably help. Source Code files are not formatted of course, and normally ENTER would be pressed at the end of each line.

In Insert mode anything typed except cursor commands and BS will be placed into the file. This includes a number of non Alpha-Numeric characters, which have a special meaning, and are ‘embedded’ commands to control formatting or printing. It is thus possible to indent, exclude from formatting, cause a printer to change character set or print mode and so on. PEN has around 16 commands to control printing.

A nice feature of PEN is that TAB characters show on the screen as a row of little dots. Since ‘TABs’ can upset formatting, it is useful to be able to ‘see’ them. (A formattable TAB character (^A) is available as an alternative.) Any area of text may be marked (^U) to exclude it from formatting, so that tables or lists that would be destroyed by normal formatting may be included. The ^U command is cancelled by a ^F command, to allow formatting to recommence. PEN also supports an Indent command (^R), which indents in steps of 4 spaces, and appears on the screen as (different) dots. This can help in building tables or lists, or just to indent the whole text. The Indent is reduced by the ^X command. If the commands are placed into the text in insert mode, variable ammounts of indent are possible. In command mode, the ^R and ^X commands operate on the whole text, so could be used to set a print margin, for example.

Some Other Commands

It is impossible to describe all of the commands in a review, so only a few will be described in any detail. Many commands are straightforward, no option commands. Potentially fatal commands are protected by ‘Are you sure?’.

Block Move/​Delete

Any block of text may be marked with a ‘backslash’ character at start and end. If the cursor is then moved to another place, the ‘M’ command will cause the marked block to be inserted at the cursor position. The origional block is not deleted. The markers may be removed by the ‘N’ command. Alternatively a “^D’ command will allow block(s) to be deleted, but PEN first checks that it has the right block, as there could be several marked blocks throughout the text. Using backslash for the move markers can be inconvient to the C programmer as these are used as remark delimters within C. The information supplied with PEN makes it an easy task to choose some other less used character instead.

Change Keyboard Case

The ‘U’ command will reverse the Keyboard case, which is very useful since this saves much operation of the Shift key, depending on the type of file being edited. With the GM827 keyboard, which has a ‘CAPS LOCK’ key, it is possible to permanently set Upper case or Lower case, or to have Lower case/​Shift upper or Upper case/​shift lower. With a NAS­COM and GEMINI keyboard in use together, a number of parallel options are possible!!

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