diff --git a/avr/usbload/config.h b/avr/usbload/config.h
index 2255d24..37005c3 100644
--- a/avr/usbload/config.h
+++ b/avr/usbload/config.h
@@ -9,14 +9,14 @@
 #define DEBUG                       1
 
 
-#define REQ_IDLE                    0
-#define REQ_UPLOAD                  1
-#define REQ_CRC                     2
+#define REQ_STATUS_IDLE                    0
+#define REQ_STATUS_UPLOAD                  1
+#define REQ_STATUS_CRC                     2
 
 #define USB_MAX_TRANS               0xff
 #define USB_CRC_CHECK               1
 
-#define BUFFER_SIZE                 0xff
+#define TRANSFER_BUFFER_SIZE        0xff
 
 
 #endif 
diff --git a/avr/usbload/crc.c b/avr/usbload/crc.c
index f7f0d7c..ab0b09f 100644
--- a/avr/usbload/crc.c
+++ b/avr/usbload/crc.c
@@ -46,9 +46,9 @@ void crc_check_memory(uint32_t top_addr,uint8_t *buffer)
     uint16_t crc = 0;
     uint32_t addr;
     uint8_t req_bank = 0;
-    for (addr = 0x000000; addr < top_addr; addr += BUFFER_SIZE) {
-        sram_read_buffer(addr, buffer, BUFFER_SIZE);
-        crc = do_crc_update(crc, buffer, BUFFER_SIZE);
+    for (addr = 0x000000; addr < top_addr; addr += TRANSFER_BUFFER_SIZE) {
+        sram_read_buffer(addr, buffer, TRANSFER_BUFFER_SIZE);
+        crc = do_crc_update(crc, buffer, TRANSFER_BUFFER_SIZE);
         if (addr && addr % 32768 == 0) {
             printf("crc_check_memory: req_bank: 0x%02x Addr: 0x%08lx CRC: 0x%04x\n",
                    req_bank, addr, crc);
@@ -63,9 +63,9 @@ uint16_t crc_check_memory_range(uint32_t start_addr, uint32_t size,uint8_t *buff
     uint16_t crc = 0;
     uint32_t addr;
     uint8_t  req_bank = 0;
-    for (addr = start_addr; addr < start_addr + size; addr += BUFFER_SIZE) {
-        sram_read_buffer(addr, buffer, BUFFER_SIZE);
-        crc = do_crc_update(crc, buffer, BUFFER_SIZE);
+    for (addr = start_addr; addr < start_addr + size; addr += TRANSFER_BUFFER_SIZE) {
+        sram_read_buffer(addr, buffer, TRANSFER_BUFFER_SIZE);
+        crc = do_crc_update(crc, buffer, TRANSFER_BUFFER_SIZE);
     }
 #if DEBUG_USB
     printf("crc_check_memory_range: Addr: 0x%08lx CRC: 0x%04x\n", addr, crc);
diff --git a/avr/usbload/main.c b/avr/usbload/main.c
index ef66877..5bf13c1 100644
--- a/avr/usbload/main.c
+++ b/avr/usbload/main.c
@@ -18,12 +18,12 @@
 
 extern FILE uart_stdout;
 
-uint8_t read_buffer[BUFFER_SIZE];
+uint8_t read_buffer[TRANSFER_BUFFER_SIZE];
 uint32_t req_addr = 0;
 uint32_t req_size;
 uint8_t req_bank;
 uint32_t req_bank_size;
-uint8_t req_state = REQ_IDLE;
+uint8_t req_state = REQ_STATUS_IDLE;
 uint8_t rx_remaining = 0;
 uint8_t tx_remaining = 0;
 uint16_t sync_errors = 0;
@@ -53,7 +53,7 @@ usbMsgLen_t usbFunctionSetup(uchar data[8])
  */
     } else if (rq->bRequest == USB_UPLOAD_ADDR) {       
                                                         
-        req_state = REQ_UPLOAD;
+        req_state = REQ_STATUS_UPLOAD;
         req_addr = rq->wValue.word;
         req_addr = req_addr << 16;
         req_addr = req_addr | rq->wIndex.word;
@@ -100,7 +100,7 @@ usbMsgLen_t usbFunctionSetup(uchar data[8])
  * -------------------------------------------------------------------------
  */
     } else if (rq->bRequest == USB_CRC_ADDR) {
-        req_state = REQ_CRC;
+        req_state = REQ_STATUS_CRC;
         req_addr = rq->wValue.word;
         req_addr = req_addr << 16;
         req_addr = req_addr | rq->wIndex.word;
@@ -121,7 +121,7 @@ usbMsgLen_t usbFunctionSetup(uchar data[8])
         tx_buffer[1] = (crc >> 8) & 0xff;
         sei();
         ret_len = 2;
-        req_state = REQ_IDLE;
+        req_state = REQ_STATUS_IDLE;
     }
 
     usbMsgPtr = data_buffer;
diff --git a/avr/usbload/usb_bulk.c b/avr/usbload/usb_bulk.c
index b40cbd7..92a48d2 100644
--- a/avr/usbload/usb_bulk.c
+++ b/avr/usbload/usb_bulk.c
@@ -17,7 +17,7 @@
 #include "crc.h"
 #include "usb_bulk.h"
 
-extern uint8_t read_buffer[BUFFER_SIZE];
+extern uint8_t read_buffer[TRANSFER_BUFFER_SIZE];
 extern uint32_t req_addr;
 extern uint32_t req_size;
 extern uint8_t req_bank;
@@ -34,7 +34,7 @@ uint8_t usbFunctionWrite(uint8_t * data, uint8_t len)
                rx_remaining, len);
         len = rx_remaining;
     }
-    if (req_state == REQ_UPLOAD) {
+    if (req_state == REQ_STATUS_UPLOAD) {
 
         rx_remaining -= len;
 #if DEBUG_USB_RAW