9260 Connecting to Sam-ba

For At91sam9260 's bootloader, there is often a problem: for clean NAND FLASH (ie no burning of anything), at91sam9260 and Sam-ba are easy to connect to, But when the burning wrote bootloader (including Bootstrap), then how also can not connect to Sam-ba.

For this problem, we first understand the next at91sam9260 and SAM-BA connection principle, regardless of any problem, first understand the principle is necessary to solve the problem.

For the connection principle, and look at the answers that are searched from the network, as described below:

The connection between the at91sam9260 and the Sam-ba is due to the fact that a piece of cured code in the chip is running before the target board is detected and the connection is established.

Suppose now that you have burned the bootstrap in, and the chip is power-up and found that there is a code to run, so that the code that does not perform on-chip curing. Therefore, you cannot establish a connection with SAM-BA. There are several main solutions to this approach:

1. On the Development Board has reserved the processing of the problem of hardware, there is a button, once the button is pressed, the test clears all the code in Flash, so that the chip to power after the implementation of its on-chip curing code. Of course, this to bootstrap inside the software support, is bootstrap detection button is pressed, if pressed to clear. In this way, on-chip power detection does not have a valid, executable code will perform on-chip curing part. The problem is solved ... ^_^

2. There is also a more unprofessional approach, but very effective. My Development Board does not have a design button and does not design the purge code in bootstrap. But I have a trick here is short-answer NAND Flash (my board does not have nor flash and data Flash) address line, about 42 feet around the location of the line. The purpose of this is to make the chip does not correctly carry the code in NAND flash into the SDRAM, so the chip's curing code will still be executed. This solves the problem that the SAM-BA cannot be connected. O (∩_∩) o haha ~

3. Because there is no nor flash and data flash on my board, it is only handled according to the NAND flash method. Other Flash follows a similar approach, so long as the code does not start correctly. Good luck to all of you ... ^_^.

Understand the principle, this problem, it is not difficult to solve, my board is the same, there is no jumping needle, but I do not use the method of the above search, but by the short connection SDRAM 7th and 8th PIN to solve, as described below:

1. Disconnect the system from power;

2. The 7th and 8th pins of the SDRAM are short-connected with tweezers, and do not loosen;

3. Power on the system, wait 4-5 seconds, loosen the tweezers, you can connect successfully, re-find the corresponding serial port in Sam-ba.

9260 connection to Sam-ba (RPM)