tms470 programmer
Some people says that Olimex wiggler can program TMS470 (on Olimex site you can find schematic), I really didn't test it, because I have bought JLINK of IAR ($250,00). PIC generally is first step because it has compilers with wizards, some resources and samples projects on net, reduced instruction set for assembler, more easy to interface (supply by +5V only, can source more current at IO pins). In TMS470 you need dual supply (1.9V and 3.3V), but has some IOs, HET timer, 16 ADC channels, CAN, J1850 ... it can work at 48MHz, has internal PLL, DMA, at end of year it go to 1M of flash memory and use an ARM7TDMI core with some advantages on PIC devices, but much more difficult to start. This processor generally is used for automotive and MIMO controllers....
Look others posts:
Maybe the better start for you is PIC and MSP430 family of TI.
For PIC and MSP is easy construct your owner programmer and with assembler you can use MPLAB for PIC (free) and for MSP use IAR Workbench (for assembler it isn't limited).
leomecma