diff -urp a/master/fsm_foe.c b/master/fsm_foe.c
--- a/master/fsm_foe.c	2013-08-15 18:11:52.000000000 +1200
+++ b/master/fsm_foe.c	2013-09-09 02:42:26.000000000 +1200
@@ -42,9 +42,9 @@
 
 /*****************************************************************************/
 
-/** Maximum time in ms to wait for responses when reading out the dictionary.
+/** Maximum time in jiffies to wait for responses when reading out the dictionary.
  */
-#define EC_FSM_FOE_TIMEOUT 3000
+#define EC_FSM_FOE_TIMEOUT (3*HZ)
 
 /** Mailbox type FoE.
  */
@@ -261,6 +261,9 @@ int ec_foe_prepare_data_send(
 
     EC_WRITE_U16(data, EC_FOE_OPCODE_DATA);    // OpCode = DataBlock req.
     EC_WRITE_U32(data + 2, fsm->tx_packet_no); // PacketNo, Password
+#ifdef DEBUG_FOE
+    EC_SLAVE_DBG(fsm->slave, 0, "sending opcode %u packet %u\n", EC_FOE_OPCODE_DATA, fsm->tx_packet_no);
+#endif
 
     memcpy(data + EC_FOE_HEADER_SIZE,
             fsm->tx_buffer + fsm->tx_buffer_offset, current_size);
@@ -298,6 +301,9 @@ int ec_foe_prepare_wrq_send(
 
     EC_WRITE_U16( data, EC_FOE_OPCODE_WRQ); // fsm write request
     EC_WRITE_U32( data + 2, fsm->tx_packet_no );
+#ifdef DEBUG_FOE
+    EC_SLAVE_DBG(fsm->slave, 0, "sending opcode %u packet %u\n", EC_FOE_OPCODE_WRQ, fsm->tx_packet_no);
+#endif
 
     memcpy(data + EC_FOE_HEADER_SIZE, fsm->tx_filename, current_size);
 
@@ -370,9 +376,8 @@ void ec_fsm_foe_state_ack_check(
 
     if (!ec_slave_mbox_check(fsm->datagram)) {
         // slave did not put anything in the mailbox yet
-        unsigned long diff_ms = (fsm->datagram->jiffies_received -
-                fsm->jiffies_start) * 1000 / HZ;
-        if (diff_ms >= EC_FSM_FOE_TIMEOUT) {
+        if (time_after(fsm->datagram->jiffies_received,
+                fsm->jiffies_start + EC_FSM_FOE_TIMEOUT)) {
             ec_foe_set_tx_error(fsm, FOE_TIMEOUT_ERROR);
             EC_SLAVE_ERR(slave, "Timeout while waiting for ack response.\n");
             return;
@@ -436,6 +441,9 @@ void ec_fsm_foe_state_ack_read(
     }
 
     opCode = EC_READ_U8(data);
+#ifdef DEBUG_FOE
+    EC_SLAVE_DBG(fsm->slave, 0, "received opcode %u\n", opCode);
+#endif
 
     if (opCode == EC_FOE_OPCODE_BUSY) {
         // slave not ready
@@ -448,6 +456,20 @@ void ec_fsm_foe_state_ack_read(
         return;
     }
 
+    if (opCode == EC_FOE_OPCODE_ERR) {
+        fsm->request->error_code = EC_READ_U32(data + 2);
+        EC_SLAVE_ERR(slave, "Received FoE Error Request (code 0x%08x).\n",
+                fsm->request->error_code);
+        if (rec_size > 6 && data[6]) {
+            uint8_t text[256];
+            strncpy(text, data + 6, min(rec_size - 6, sizeof(text)));
+            text[sizeof(text)-1] = 0;
+            EC_SLAVE_ERR(slave, "FoE Error Text: %s\n", text);
+        }
+        ec_foe_set_tx_error(fsm, FOE_OPCODE_ERROR);
+        return;
+    }
+
     if (opCode == EC_FOE_OPCODE_ACK) {
         fsm->tx_packet_no++;
         fsm->tx_buffer_offset += fsm->tx_current_size;
@@ -571,6 +593,9 @@ int ec_foe_prepare_rrq_send(
     EC_WRITE_U16(data, EC_FOE_OPCODE_RRQ); // fsm read request
     EC_WRITE_U32(data + 2, 0x00000000); // no passwd
     memcpy(data + EC_FOE_HEADER_SIZE, fsm->rx_filename, current_size);
+#ifdef DEBUG_FOE
+    EC_SLAVE_DBG(fsm->slave, 0, "sending opcode %u\n", EC_FOE_OPCODE_RRQ);
+#endif
 
     if (fsm->slave->master->debug_level) {
         EC_SLAVE_DBG(fsm->slave, 1, "FoE Read Request:\n");
@@ -601,6 +626,9 @@ int ec_foe_prepare_send_ack(
 
     EC_WRITE_U16(data, EC_FOE_OPCODE_ACK);
     EC_WRITE_U32(data + 2, fsm->rx_expected_packet_no);
+#ifdef DEBUG_FOE
+    EC_SLAVE_DBG(fsm->slave, 0, "sending opcode %u packet %u\n", EC_FOE_OPCODE_ACK, fsm->rx_expected_packet_no);
+#endif
 
     return 0;
 }
@@ -709,9 +737,8 @@ void ec_fsm_foe_state_data_check(
     }
 
     if (!ec_slave_mbox_check(fsm->datagram)) {
-        unsigned long diff_ms = (fsm->datagram->jiffies_received -
-                fsm->jiffies_start) * 1000 / HZ;
-        if (diff_ms >= EC_FSM_FOE_TIMEOUT) {
+        if (time_after(fsm->datagram->jiffies_received,
+                fsm->jiffies_start + EC_FSM_FOE_TIMEOUT)) {
             ec_foe_set_tx_error(fsm, FOE_TIMEOUT_ERROR);
             EC_SLAVE_ERR(slave, "Timeout while waiting for ack response.\n");
             return;
@@ -739,7 +766,8 @@ void ec_fsm_foe_state_data_read(
         )
 {
     size_t rec_size;
-    uint8_t *data, opCode, packet_no, mbox_prot;
+    uint32_t packet_no;
+    uint8_t *data, opCode, mbox_prot;
 
     ec_slave_t *slave = fsm->slave;
 
@@ -775,10 +803,16 @@ void ec_fsm_foe_state_data_read(
     }
 
     opCode = EC_READ_U8(data);
+#ifdef DEBUG_FOE
+    EC_SLAVE_DBG(fsm->slave, 0, "received opcode %u\n", opCode);
+#endif
 
     if (opCode == EC_FOE_OPCODE_BUSY) {
+        fsm->rx_expected_packet_no--;
         if (ec_foe_prepare_send_ack(fsm, datagram)) {
             ec_foe_set_rx_error(fsm, FOE_PROT_ERROR);
+        } else {
+            fsm->state = ec_fsm_foe_state_sent_ack;
         }
         return;
     }
@@ -787,9 +821,10 @@ void ec_fsm_foe_state_data_read(
         fsm->request->error_code = EC_READ_U32(data + 2);
         EC_SLAVE_ERR(slave, "Received FoE Error Request (code 0x%08x).\n",
                 fsm->request->error_code);
-        if (rec_size > 6) {
+        if (rec_size > 6 && data[6]) {
             uint8_t text[256];
             strncpy(text, data + 6, min(rec_size - 6, sizeof(text)));
+            text[sizeof(text)-1] = 0;
             EC_SLAVE_ERR(slave, "FoE Error Text: %s\n", text);
         }
         ec_foe_set_rx_error(fsm, FOE_OPCODE_ERROR);
@@ -804,9 +839,10 @@ void ec_fsm_foe_state_data_read(
         return;
     }
 
-    packet_no = EC_READ_U16(data + 2);
+    packet_no = EC_READ_U32(data + 2);
     if (packet_no != fsm->rx_expected_packet_no) {
-        EC_SLAVE_ERR(slave, "Received unexpected packet number.\n");
+        EC_SLAVE_ERR(slave, "Received packet number %u, expected %u.\n",
+                packet_no, fsm->rx_expected_packet_no);
         ec_foe_set_rx_error(fsm, FOE_PACKETNO_ERROR);
         return;
     }