from nx_crypto_ec.c:296
static NX_CRYPTO_CONST HN_UBASE _nx_crypto_ec_secp521r1_a[] =
{
HN_ULONG_TO_UBASE(0xFFFFFFFC), HN_ULONG_TO_UBASE(0xFFFFFFFF),
HN_ULONG_TO_UBASE(0xFFFFFFFF), HN_ULONG_TO_UBASE(0xFFFFFFFF),
HN_ULONG_TO_UBASE(0xFFFFFFFF), HN_ULONG_TO_UBASE(0xFFFFFFFF),
HN_ULONG_TO_UBASE(0xFFFFFFFF), HN_ULONG_TO_UBASE(0xFFFFFFFF),
HN_ULONG_TO_UBASE(0xFFFFFFFF), HN_ULONG_TO_UBASE(0xFFFFFFFF),
HN_ULONG_TO_UBASE(0xFFFFFFFF), HN_ULONG_TO_UBASE(0xFFFFFFFF),
HN_ULONG_TO_UBASE(0xFFFFFFFF), HN_ULONG_TO_UBASE(0xFFFFFFFF),
HN_ULONG_TO_UBASE(0xFFFFFFFF), HN_ULONG_TO_UBASE(0xFFFFFFFF),
HN_ULONG_TO_UBASE(0x000001FF)
};