set-iomap command

The set-iomap BASIC program allows translatable input and output for each port on the system.


set-iomap port.number{,item-ID} ([i|o|ri|ro]


port.number  Specifies the number of the port for which the iomap is being set.
item-ID Item-ID of the user-defined keyboard item. It must be numeric, and is not required when used with any of these options: ir, ri, or, or ro.
i Installs input keyboard. Character translation occurs before reaching input handling code, such as BASIC in.
o Installs output keyboard. Character translation occurs before reaching output handling code, such as BASIC print.
ir or ri Removes an installed input keyboard.
or or ro Removes an installed output keyboard.

There is a file in the dm account called iomap-file. This file contains keyboard items that are defined by users. The item-ID should be numeric and should be in the range of 0 <= item-ID <= 2147483647. The keyboard item has 34 attributes and has this format:

attr 0 Item-ID
attr 1 User comments
attr 2 to 33 ASCII code of characters from 0 to 127 in ASCII hexadecimal format. For example: character a has its ASCII code as x'41' and should be entered in the item as '41'. Each attribute from 2 to 33 has exactly eight entries each. Each entry must be two characters and there should be no quotes or spaces surrounding any number. In other words, each entry should look like a 16 digit hexadecimal number. User can put their comments after the eighth entry on that attribute.

The example below shows how to translate the character A to B:

  • ASCII code of A is x'41' = d'65'

  • ASCII code of B is x'42' = d'66'

  • 65 mod 8 = 8 with remainder 1

  • Translated character, which is B, should be entered at attribute 8+2= 10 and at column 1*2+1=3 as 42. The reason that 2 is added to 8 is because counting begins at 0 and attribute 1 is used for comments.


open "iomap-file" then
   a = "Sample IOMap"
   for b = 0 to 127
      a < 0 + int( b / 8 ) > := dtx( b ) "r%2"
   next b
   write a on "12345"