do i have to "eraseall" first?

[??]

dear david,

thanks for your help,

now it report many "magic bitmask not found"
do i have to do something like "eraseall /dev/mtdblock1" before "cp test.img
/dev/mtdblock1"?

thanks in advanced!:)

best regards,
kevin

----following message
log------------------------------------------------------
jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x00298014:
0xa3dc in
stead
jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x00298018:
0xccfe in
stead
jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x0029801c:
0xd1b5 in
stead
jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x00298020:
0xf8fd in
stead
jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x00298024:
0xb452 in
stead
Further such events for this erase block will not be printed
nand_read_ecc: Failed ECC read, page 0x00007fc0
nand_read_ecc: Failed ECC read, page 0x00007fc0
nand_read_ecc: Failed ECC read, page 0x00007fc1
nand_read_ecc: Failed ECC read, page 0x00007fc1
nand_read_ecc: Failed ECC read, page 0x00007fc2
nand_read_ecc: Failed ECC read, page 0x00007fc2
nand_read_ecc: Failed ECC read, page 0x00007fc3
nand_read_ecc: Failed ECC read, page 0x00007fc3
jffs2_scan_empty(): Read 0x1000 bytes at 0x00df8000 returned -5
mount: wrong fs type, bad option, bad superblock on /dev/mtdblock1,
       or too many mounted file systems