...what money can buy:
Commercial HC12 Development Tools: Compilers, Debuggers, Emulators
ICC12 ANSI-C Cross-Compiler with Windows IDE by ImageCraft
ICC12 - Information in German
NoICE12 HC12 Remote Debugger with C-Source Level Support
Made in France: COSMIC C for 68HC12 - Cosmic Software is one of the HC12 C-Compiler pioneers. The compiler is said to be rock solid, so it only depends on your budget...
Cosmic's US office (for those not so familiar with French :-)
COSMIC@Elektronikladen - German info
Metrowerks CodeWarrior for HC12 and HCS12 - C/C++/compactC++ Compiler, Debugger, Simulator, IDE
Made in Sweden: IAR Systems Embedded Workbench, Integrated C Compiler, C-Spy Debugger are available for the HC12
Made in Germany: TRACE32 Microprocessor Development Tools from Lauterbach GmbH
iC3000 ActiveEmulator and GUI (WinIDEA) by iSystem GmbH
iONE ONchipEmulator for BDM-based systems by iSystem GmbH
Very British: FlexBDM Debugger from Noral Micrologics
Noral also offers the Flex-Sim/Cpu12 Debugger (free trial download)
Nohau Corporation makes both BDM as well as "full featured" Emulators for the HC12/HCS12. Also check out the Publications and Documents section on their site
Sid Price's StingRay BDM12 Debugger
DProbeHC12, DProbeS12 - In-Circuit Emulators by Hitex
TantinoS12 - compact BDM debug hardware by Hitex
Processor Expert - Product Releases for HCS12 - component oriented application builder, generates code using "Embedded Beans"
Several HC12 Tools by P&E Microcomputer Systems
RTXC Real Time Kernel by Quadros Systems Inc.
BDM12 Source Code Debugger HC12ICD by J. Krummsdorf, supports HC12 and HCS12, trial version available
MPE Forth 6 cross compiler is available with VFX code generator for 68HC12
iCall Software Visualization and Stack Analyzer from AbsInt include versions for 68HC12/HCS12
Encirq 3e is a tool suite for creating data management functions for embedded systems
Ein umfangreiches Tutorial zur DEV12 Toolchain erläutert das Zusammenspiel zwischen C-Compiler (ICC12), Debugger (NoICE12), BDM-Pod (ComPOD12) und HCS12 Zielhardware (CardS12.D64 mit TwinPEEKs Monitor) während der Anwendungsentwicklung