# HG changeset patch
# User Paul Boddie <paul@boddie.org.uk>
# Date 1421789059 -3600
# Node ID 72f6d830b176c4368042c97e665421b1df8d9941
# Parent  df3b4c8c3fe5d3c5b10e50db6108c51f2fbc559b
Introduced convenience functions and added some failure handling.

diff -r df3b4c8c3fe5 -r 72f6d830b176 upload.py
--- a/upload.py	Tue Jan 20 22:23:38 2015 +0100
+++ b/upload.py	Tue Jan 20 22:24:19 2015 +0100
@@ -1,12 +1,41 @@
 #!/usr/bin/env python
 
 from serial import Serial
+from time import sleep
 import sys
 
+port = "/dev/ttyUSB0"
+rate = 115200
+
+def openPort():
+    global s
+    s = Serial(port, rate)
+    s.setTimeout(5)
+    s.readline()
+
+def closePort():
+    global s
+    s.close()
+    s = None
+
+def writeToPort(data):
+    s.write(data)
+    s.flush()
+    print >>sys.stderr, data.rstrip()
+
+def readFromPort():
+    resp = s.readline().rstrip("\r\n")
+    if resp == "?":
+        resp = s.readline().rstrip("\r\n")
+    return resp
+
 def console():
     try:
         while 1:
-            s.write(raw_input("> ") + "\n")
+            cmd = raw_input("> ")
+            if cmd:
+                s.write(cmd + "\n")
+                s.flush()
             print s.readline().rstrip("\r\n")
     except EOFError:
         print "Session closed."
@@ -20,8 +49,8 @@
 
     print >>sys.stderr, "Erasing sector", sector, "..."
 
-    s.write("S%x\n" % sector)
-    resp = s.readline().rstrip("\r\n")
+    writeToPort("S%x\n" % sector)
+    resp = readFromPort()
     if resp != "S":
         print >>sys.stderr, "Sector %d erase failed: %s" % (sector, resp)
         return False
@@ -32,28 +61,32 @@
     while i < 0x4000:
         value = ord(data[i])
         addr = (sector << 14) | i
-        s.write("P%04x%02x\n" % (addr, value))
-        print >>sys.stderr, "P%04x%02x" % (addr, value)
-        resp = s.readline().rstrip("\r\n")
-        if resp != "P":
-            print >>sys.stderr, "Program of location %04x failed: %s" % (addr, resp)
-            return False
-        #s.write("R%04x\n" % addr)
-        #print >>sys.stderr, "R%04x" % addr
-        #readvalue = s.readline().rstrip("\r\n")
-        #if readvalue != ("%X" % value):
-        #    print >>sys.stderr, "Program of location %04x failed: %s read for %s written." % (addr, readvalue, "%X" % value)
-        #    return False
+
+        while 1:
+            writeToPort("P%04x%02x\n" % (addr, value))
+            resp = readFromPort()
+            if resp != "P":
+                print >>sys.stderr, "Program of location %04x failed: %s" % (addr, resp)
+                closePort()
+                sleep(5)
+                openPort()
+                writeToPort("R%04x\n" % addr)
+                resp = readFromPort()
+                if resp == ("%X" % value):
+                    break
+                print >>sys.stderr, "Read from location %04x failed: %s" % (addr, resp)
+                closePort()
+                sleep(5)
+                openPort()
+            else:
+                break
+
         i += 1
 
     return True
 
 if __name__ == "__main__":
-    port = "/dev/ttyUSB0"
-    rate = 115200
-
-    s = Serial(port, rate)
-    s.readline()
+    openPort()
 
     if "-i" in sys.argv:
         console()