INFORMATION: The following table gives you ROMed boot-up applications according to the pin setting after a power-up or a reset.
Pin Name
Level
Level
Default State after reset
TST
1
1
Pull-down
PA0/PGMEN0
1
1
Pull-up
PA1/PGMEN1
1
1
Pull-up
PA2/PGMEN2
0
1
Pull-up
Boot up Application ->
FFPI
SAM-BA Boot
Other pin setting about TST, PA[0,1,2]/PGMEN|0,1,2] are reserved.
SYSTEM RECOVERY PROCEDURE:
Shut down the board,
Before to power up the board, the TST, PA0/PGMEN0, PA1/PGMEN1, and PA2/PGMEN2 signals must be set (see the table on the left which gives you an overview about these pins). On the AT91SAM7S-EK evaluation board, put only the JP5 jumper to set the TST signal (by default, others signal are set thanks to the embedded pull-up resistors).
Power up the board and wait 10 secondes,
Shut down the board and remove the JP5 jumper,
Power up the board: The board is now working with the SAM-BA Boot application from the flash and waiting connection through USB port.
IMPORTANT: THIS SYSTEM RECOVERY PROCEDURE CANNOT BE EXECUTED IF THE FLASH SECURITY BIT IS SET.
INFORMATION: What has the Recovery Procedure Performed ?
The recovery procedure has: - Forced the AT91SAM7S to boot from its internal ROM (first power up with TST = 1), - Unlocked the fisrt two regions, - Erased the first two regions (8 KBytes only), - Copied the SAM-BA Boot to the first 4.5 kbytes Flash memory area, - Locked these regions, - Start the SAM-BA Boot (second power up with TST = 0). At this level, the target is working out of internal Flash with SAM-BA Boot and waiting serial connection from SAM-PRO through its USB socket.
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