| ??? 10/03/07 18:40 Read: times |
#145309 - bootloader corruption? Responding to: ???'s previous message |
Cory L. Spackman said:
We have been considering the AT89C51AC2 and AT89C51ID2. One major flaw I see in these is that errant firmware could overwrite the factory bootloader and render the device little more than an expensive paperweight. Huh, do you have a proof of such corruption? Although I believe the bootloader does indeed sit in FLASH, IIRC the datasheets (at least for the 'RD2/'ED2) say otherwise ("ROM bootloader"), and I believe Atmel made significant effort to protect the bootloader from being rewriteable from the user code. Of course, if you do have evidence for something different, it's an another case. Cory L. Spackman said:
We have been looking seriously at the uPSD parts, and they have a bootloader sector that can be protected via JTAG, What difference does JTAG exactly make? Cory L. Spackman said:
but given that we've decided to offload the USB to a 32 bit micro, and we don't really need a PLD, the complexity of the uPSD seems somewhat unnecessary. Granted, the 10 MIPS speed and plentiful IO may come in handy. The core of uPSD32xx series is a pretty standard 12-clocker, without the bells and whistles of the 33xx/34xx 4-clockers; but that also means that the 32xx-s are much closer to the original '51 hence simpler and faster to manage. And, once you figure out how to use the configuration tool, it turns to be a pretty standard '51 derivative with plenty of FLASH and relatively much onchip XRAM, with as few extra I/O pins. The PLD is not that powerful, either, being roughly the equivalent of two GAL16V8-s or similar. JW |
| Topic | Author | Date |
| IAP/ISP bootloader destruction vulnerability | 01/01/70 00:00 | |
| suggestions/answers | 01/01/70 00:00 | |
| certainly not the P89V51Rx2 | 01/01/70 00:00 | |
| Different devices ? | 01/01/70 00:00 | |
this is EXACTLY how it works with the Atmels... | 01/01/70 00:00 | |
| bootloader corruption? | 01/01/70 00:00 |