| ??? 04/28/09 08:03 Read: times |
#164888 - Too wide question Responding to: ???'s previous message |
Bing Logarth said:
I am not sure though, does AT91RM9200 has a built in bootloader? That is a too wide question to ask. A boot loader doing what? Some processors may have a big boot loader, but limited to features the manufacturer likes. Some may have a tiny boot loader, but allowing you to add a secondary boot loader optimized for your requirements. You then decide if you should waste code space for supporting firmware downloads from Ethernet, USB, RS232, SPI, SD-memory, ... By the way - what was the reason you directly jumped for the AT91RM9200? Without picking up the datasheet, I would suspect that it only has a USB device. If you need both USB host and USB device, then you must either look for USB OTH (if it is enough that one USB interface is selectable host/device) or you have to do your selection among chips with at least two USB interfaces, and then look in the datasheet if any of them is a host. Another thing - don't you think you should look for more than 16kB of RAM if you are going to use both USB and Ethernet? Take your time, and don't jump at the first chip you see with for UART. Write down your requirements on a paper and then note down interesting chips. Then use the datasheet to check off the requirements one-by-one. If you then have multiple possibilities, then look for the availability and price and generally select the newer chip. |
