LPC1768 - vector table size

You are right. Now I found in the datasheet:
"The vector table may be located anywhere within the bottom 1 GB of Cortex-M3 address
space. The vector table should be located on a 256 word (1024 byte) boundary to insure
alignment on LPC17xx family devices."

Thanks.

You are right. Now I found in the datasheet:
"The vector table may be located anywhere within the bottom 1 GB of Cortex-M3 address
space. The vector table should be located on a 256 word (1024 byte) boundary to insure
alignment on LPC17xx family devices."

Thanks.

You didn't read everything in the user manual.

Look for example at figure 3 LPC17xx system memory map.

Does the vector table seem to be 1 kB large?

You may also look at table 51 and see if you find any vectors spanning the full kilobyte. 1kB has room for a lot of interrupt vectors, but the NVIC doesn't mention such a large number of vectors.