“RAM check failed” when using j-Link to erase chip or readback

Question

I closed SWD and JTAG by acident so that I can't download new program into developboard by j-Link.Then I try using j-flash ARM to erase chip, and error comes like this:

Connecting ...
 - Connecting via USB to J-Link device 0
 - J-Link firmware: V1.20 (J-Link ARM V8 compiled Dec  1 2009 11:42:48)
 - JTAG speed: 2000 kHz (Auto)
 - Initializing CPU core (Init sequence) ...
    - Executing Reset (0, 0 ms)
    - Initialized successfully
 - JTAG speed: 2000 kHz (Auto)
 - Connected successfully
Reading entire flash chip ...
 - 64 sectors, 1 range, 0x8000000 - 0x800FFFF
 - ERROR: RAM check failed @ address 0x20000000.
 - ERROR: Write: 0x03020100 07060504
 - ERROR: Read: 0xAAAAAAAA AAAAAAAA
 - ERROR: (0 bytes of RAM have been checked successfully)
 - ERROR: Failed to read back target memory
Disconnecting ...
 - Disconnected

I don't know how to use BOOT0 and BOOT1 to get into ISP mode. BOOT0 is connected to GND.

Answer 1

Post some information about your environment.

Are you using IAR EWARM? If you're not, you should download the size-limited trial version. Then, load one of the basic program examples, and try to flash it to your board.

What board are you using? And what do you mean you "closed" SWD and JTAG? I'm not sure what that refers to...jumpers? options window?

Help us out here.