Keil Devevlopment tools have always been at the front of the field. for 8051 and 16* family with the uVision IDE and Simulator. The JTAG -Ulink completes the suite.
Keil's UV3 IDE and ARM Simulator coupled with ARM corp's Cand C++ compiler Also intergrates with the Keil RT-Lib of RTOS, USB, TCP/IP and file system > Link to
The Keil C16* family compiler covering C161 tro C167 the XC varients and the ST10 versions is the leading compiler for these families > Link to