EC_BUF_SZ
count = EC_BUF_SZ - m0->m_pkthdr.len;
#define EC_PKT_MAXTDOFF (EC_BUF_SZ - (ETHER_MIN_LEN - ETHER_CRC_LEN)) /* max xmit doff (min size) */
#define EC_PKT_MAXRDOFF (EC_BUF_SZ - EC_PKT_RDOFF) /* max packet doff (max size) */
uint8_t ec_tbuf[EC_BUF_SZ]; /* transmit buffer */
uint8_t ec_abuf[EC_BUF_SZ]; /* receive buffer A */
uint8_t ec_bbuf[EC_BUF_SZ]; /* receive buffer B */
#define ECREG_ABUF (ECREG_TBUF + EC_BUF_SZ)
#define ECREG_BBUF (ECREG_ABUF + EC_BUF_SZ)
#define ECREG_BANK_SZ (ECREG_BBUF + EC_BUF_SZ)