Following a comment from Sivan, I have produced an upgraded version of the  IAST or ISO 15919 keyboard. Sometimes it is useful to write Sanskrit and other Indic languages in a form that is unambiguous but can be easily read by people who know the Latin alphabet. The standard ways of doing this are with IAST or ISO 15919. The two schemes are almost identical. An example is ताण्डव which can b written as Tāṇḍava. I have produced a windows keyboard that contains the necessary diacritics (accent marks). The normal keys are assigned the same as the standard UK keyboard, only the characters accessed with the AltGr and Shift-AltGr change, as do some characters using the caps lock.

The changes to the keyboard are as follows. Firstly in the previous version I had placed the ṅ character as AltGr-n. Most other keys used the AltGr to indicate the dot underneath, and this difference was confusing. I have therefore swapped the ṅ and ṇ so that AltGr-n gives the ṇ character. Apart from anything else it makes typing Tāṇḍava a lot easier!

Also Sivan pointed out that I had missed the visarga from the keyboard. This is the h with a dot ḥ. I have placed this as AltGr-h  Here is the layout of keys with AltGr (or Ctrl-Alt does the same if your keyboard doesn’t have an AltGr key)

Indic transliteration layout with AltGr

The Shift-AltGr keys are as expected, showing the capitalised versionsof the same letters.

Sivan also asked for the vowels with circumflex, used when a long vowel appears because of two combining vowels, e.g. â, ê, etc. I was not sure where to put them, as the AltGr-a is used for ā, etc.. I came up with three options:

1. Using AltGr and some unused character. This would be very easy to type but hard to remember.
2. Use dead keys, so that Shift-6 (^) followed by a would produce â, etc. This would be inconsistant with the handling of other Diacritics.
3. Use the caps lock mode, so that when caps lock is on the keys produce different characters. This is easy to remember, with caps lock on ‘a’ prints as ‘â’, and Shift-a as Â, etc. This seems a good compromise, but does mean that caps lock cannot be used for typing capitals easily.

I hardly ever use caps lock so this is the option I selected. I will see how this works out in practice, but here are the layouts:

Indic Transliteration with caps lock

The shifted version gives the capital versions of these letters:

Indic transliteration with Caps lock on and Shift pressed

Installing the Keyboard

If you have a previous version of this driver installed you must remove it before installing this one. To do that:

1. Configure your keyboard settings in control panel to remove the old driver (Control Panel->Clock, Language, and Region->change keyboard and other input methods->change keyboard->Remove).
2. De-install the driver by running setup.exe in the old package.

This keyboard driver can be loaded the same way as the bolnagri layout described in a previous article. The files are available here with the package zip file and the keyboard creator source file available for download and free use.

Please let me know if you have any suggestions of how this keyboard layout could be improved.