I wanted to ask if there is anyone that can comment on the feasibility of having an 8051 architecture processor perform coordinate system conversions in real time. Say for example you had a microcontroller connected to a GPS receiver that provided location information in latitide and longitude in an ASCII string or strings from an RS232 port. But lets say you wanted to display that Earth positional information in another format. One format that comes to mind is one used by military organizations called MGRS (Military Grid Reference System).

I have used Google to search out information on Earth coordinate systems and I see that there is a tendancy to use C code with double variables to do coordinate conversions. Are conversions using C float type variables even at all useful for accurate coordinate system conversions? I use the Keil C-51 compiler and it only supports the float data type. (If you specify double it does not puke but instead aliases such variables back to float).

If coordinate systems conversion is at all feasible I wonder just how long it takes to do a conversion? I could anticipate the use of a Silicon Labs C8051F126 with 128K of FLASH & 8K of onboard XRAM running at 22.1814 MHz or faster. How long would something like this take to compute on a bog standard 12 clocker 89C52 at say 11.0592 MHz?

Michael Karas

PS...Incidently the full project actually would require conversion both ways between coordinate systems because the user has an inteface via a keypad to enter way points in a coordinate system format that is equivalent to the format he/she sees on the LCD display.

MJK