Question: The C2xx User's Guide states that the code for the boot loader is stored on chip. Where on the chip is it stored? Is there some ROM that is not accessible to the user, and so is not shown in the datasheet or databook? Where is this boot loader code mapped in program space?

Answer: The bootloader is not in ROM, but in a PLA at address ff00. To look at it, make sure your emuinit file includes this address range. Normally on our devices that have boot loader, we put a very small ROM or a PLA to store the boot loader instructions. If the boot loader code is very small and there is no ROM on the chip, we would tend to use a PLA. Suppose you have the boot pin asserted and br- connected to an EPROM in global space and with the xDS510 hooked to a C203 and a boot image at an address such as 8000h (e.g., EPROM) You can execute a RESET command. At address 0 in PS, you will see an inst b ff00. You can then single step through the bootloader and watch it copy the code to PS. If you are copying the boot table to address 0 in external RAM, there is no problem bcs the first branch (at addr 0) has long since been executed. The users guide has the bootloader code in it and you can see it is a short piece of code. At the end of the code, it executes an int0 so -have the reset vector at address 0.