r4 dsi soft- and firmware

The R4 DSi does not function without additional software. This piece of software is called firmware. The R4 DSi's firmware is updated now and then, so that it will function with all games that are placed onto the internet.
Version 1.54 of the r4 dsi firmware can be downloaded here.
Always visit the r4 dsi official website, to see if there is a new firmware available.