git.rot13.org Git - goodfet/blob - client/GoodFETEM260.py

   1 #!/usr/bin/env python
   2 # GoodFET EM260 Radio Client
   3 #
   4 # (C) 2010 Travis Goodspeed <travis at radiantmachines.com>
   5 #
   6 # This code is being rewritten and refactored.  You've been warned!
   7
   8 # The EM260 is almost textbook SPI, except that the response cannot be
   9 # read until after the nHOST_INT pin of the EM260 drops low and a dummy
  10 # byte is read.  That is, the sequence will look like the following:
  11
  12 # Transmit Host->Slave Data
  13 # while(nHOST_INT); //Sleep until ready.
  14 # Recv Dummy Byte
  15 # Recv Slave->Host Data
  16
  17 # The delay is mandatory.
  18
  19 import sys, time, string, cStringIO, struct, glob, serial, os;
  20
  21 from GoodFETSPI import GoodFETSPI;
  22
  23 class GoodFETEM260(GoodFETSPI):
  24     EM260APP=0x01;
  25     seq=0;
  26     def EM260trans(self,data,retry=1):
  27         """Exchange data by EM260 SPI. (Slightly nonstandard.)"""
  28
  29         if retry==0:
  30             #Retries exceeded.  Send a trivial command to clear error.
  31             data=[0x0A,0xA7];
  32         self.writecmd(0x01,0x82,len(data),data);
  33
  34
  35         try:
  36             reply=ord(self.data[0]);
  37             if(reply==0x00):
  38                 #print "Warning: EM260 rebooted.";
  39                 return self.EM260trans(data,retry-1);
  40             if(reply==0x02):
  41                 #print "Error: Aborted Transaction.";
  42                 return self.EM260trans(data,retry-1);
  43             if(reply==0x03):
  44                 print "Error: Missing Frame Terminator.";
  45                 return self.data;
  46             if(reply==0x04):
  47                 print "Error: Reserved Error.  (Access denied?)";
  48                 return self.data;
  49         except:
  50             print "Error in EM260trans.";
  51         return self.data;
  52
  53     def EZSPtrans(self,frame):
  54         """Send an EZSP frame."""
  55         data=self.EM260trans([0xFE,len(frame)+2,
  56                               self.seq,0x00,
  57                               ]+frame+[
  58                               0xA7]);
  59         #s="";
  60         #for foo in data:
  61         #    s=s+"%02x " % ord(foo);
  62         #print s;
  63         if ord(data[0])!=0xFE:
  64             print "EZSP error: 0x%02x" % ord(data[0]);
  65         if frame[0]!=ord(data[4]):
  66             print "EZSP warning: Command 0x%02x returned type 0x%02x." % (
  67                 frame[0],ord(data[4]));
  68         self.seq=self.seq+1;
  69         return data;
  70         #return ord(data[0]);
  71
  72     def peek8(self,adr):
  73         """Read a byte from the given address."""
  74
  75         data=self.EZSPtrans([0x47,adr&0xFF]);
  76
  77         return ord(data[0]);
  78
  79     def rand16(self):
  80         """Read a byte from the given address."""
  81
  82         data=self.EZSPtrans([0x49]);
  83         return ord(data[6])+(ord(data[7])<<8);
  84
  85     def info(self):
  86         """Read the info bytes."""
  87         print "Ember EM26 Z-Stack SPI Module.";
  88         version=self.EM260spiversion();
  89         status=self.EM260spistatus();
  90         print "Version: %i" % (version);
  91         print "Status:  %s" % (["dead","alive"][status]);
  92     def EM260spiversion(self):
  93         """Read the SPI version number from EM260."""
  94         data=self.EM260trans([0x0A,0xA7]);
  95         version=ord(data[0]);
  96
  97         if version==0x00:
  98             return self.EM260spiversion();
  99         if version==0x02:
 100             return self.EM260spiversion();
 101         if not version&0x80:
 102             print "Version misread.";
 103             return 0;
 104         return version&0x7F;
 105
 106     def EM260spistatus(self):
 107         """Read the status bit."""
 108         data=self.EM260trans([0x0B,0xA7]);
 109         status=ord(data[0]);
 110
 111         if status==0x00:
 112             return self.EM260spistatus();
 113         if status==0x02:
 114             return self.EM260spistatus();
 115         if not status&0x80 and status&0x40:
 116             print "Status misread.";
 117             return 0;
 118         return status&1;