AVR programming on 11-CURRENT

[Jonathan Anderson]

Good morning,

I'm attempting to program a Pololu 3pi AVR-based robot [1] using an 
STK500v2-compatible programmer [2] on 11-CURRENT. I'm not having a lot 
of success. I've seen a discussion from 2012 on this list [3], but that 
seems to be a different issue: I'm using the same command lines that 
apparently worked then with no success now.

I've tried using the same avrdude command line as I would use from a 
Linux workstation, but with /dev/ttyACM0 replaced with /dev/cuaU0:

```
$ avrdude -p m328p -c stk500v2 -P /dev/cuaU0 -Uflash:w:assign0.hex:a
```

This command hangs indefinitely. When I enable more verbosity I see:

```
$ avrdude -vvvv -pm328p -c stk500v2 -P /dev/cuaU0 -t

avrdude: Version 6.1, compiled on Oct 24 2015 at 06:47:13
          Copyright (c) 2000-2005 Brian Dean, http://www.bdmicro.com/
          Copyright (c) 2007-2014 Joerg Wunsch

          System wide configuration file is 
"/usr/local/etc/avrdude.conf"
          User configuration file is "/home/jon/.avrduderc"
          User configuration file does not exist or is not a regular 
file, skipping

          Using Port                    : /dev/cuaU0
          Using Programmer              : stk500v2
avrdude: Send: . [1b] . [01] . [00] . [01] . [0e] . [01] . [14]
```

Using trace, I can confirm that the relevant bytes are being written to 
the file descriptor, but then avrdude goes into a loop of `select()`'ing 
the descriptor and reading 0 bytes:

```
8440 avrdude  GIO   fd 2 wrote 65 bytes
        "avrdude: Send: . [1b] . [01] . [00] . [01] . [0e] . [01] . [14]
        "
   8440 avrdude  RET   write 65/0x41
   8440 avrdude  CALL  write(0x3,0x7fffffffdad0,0x7)
   8440 avrdude  GIO   fd 3 wrote 7 bytes
        0x0000 1b01 0001 0e01 14                        |.......|

   8440 avrdude  RET   write 7
   8440 avrdude  CALL  select(0x4,0x7fffffffdae8,0,0,0x7fffffffdb68)
   8440 avrdude  RET   select 1
   8440 avrdude  CALL  read(0x3,0x7fffffffdbef,0x1)
   8440 avrdude  GIO   fd 3 read 0 bytes
        ""
   8440 avrdude  RET   read 0
   8440 avrdude  CALL  select(0x4,0x7fffffffdae8,0,0,0x7fffffffdb68)
   8440 avrdude  RET   select 1
   8440 avrdude  CALL  read(0x3,0x7fffffffdbef,0x1)
   8440 avrdude  GIO   fd 3 read 0 bytes
        ""
```

For reference, here is my dmesg output when I first plug in the 
programmer:

```
ugen2.8: <Pololu Corporation> at usbus2
umodem0: <Pololu Corporation Pololu USB AVR Programmer, class 239/2, rev 
2.00/1.07, addr 8> on usbus2
umodem0: data interface 1, has no CM over data, has no break
umodem1: <Pololu Corporation Pololu USB AVR Programmer, class 239/2, rev 
2.00/1.07, addr 8> on usbus2
umodem1: data interface 3, has no CM over data, has no break
```

After I kill avrdude, the USB device disconnects and re-connects:

```
umodem0: at uhub5, port 3, addr 8 (disconnected)
umodem1: at uhub5, port 3, addr 8 (disconnected)
umodem0: <Pololu Corporation Pololu USB AVR Programmer, class 239/2, rev 
2.00/1.07, addr 8> on usbus2
umodem0: data interface 1, has no CM over data, has no break
umodem1: <Pololu Corporation Pololu USB AVR Programmer, class 239/2, rev 
2.00/1.07, addr 8> on usbus2
umodem1: data interface 3, has no CM over data, has no break
```

Any ideas what might be going wrong here? Does anybody use 11-CURRENT 
with STK500v2-compatible programmers successfully?

Thanks,


Jon

[1] https://www.pololu.com/product/975
[2] https://www.pololu.com/product/1300
[3] http://comments.gmane.org/gmane.os.freebsd.questions/288334

--
Jonathan Anderson
jonathan at FreeBSD.org