[avrdude-dev] Problem with TPI and "serbb" mode

[Wayne Holder]

I'm trying to use AVRDUDE on macOS 0.14.2 to communicate with an ATTiny10
that's connected an FTDI breakout board like this:

TXD  --[1K]---+
              |   +----------------------+
CTS  ---------+---| TPI DATA (1)   RESET | ------+
GND  -------------| GND              VCC | ---+  |
DTR  -------------| TPI CLK           NC |    |  |
                  +----------------------+    |  |
                                              |  |
VCC  -----------------------------------------+  |
                                                 |
RTS  --------------------------------------------+

Note: adapted from http://irq5.io/2010/07/15/programming-the-attiny10/

and using this as the definition for the programmer:

programmer
  id    = "ftdiprog";
  desc  = "FTDI serial port banging, reset=rts sck=dtr mosi=txd miso=cts";
  type  = "serbb";
  miso  = ~8;
  reset = ~7;
  sck   = ~4;
  mosi  = ~3;
;

Note: passed using the - C + switch in file ftdiprog.conf

But, when I use the following invocation (paths removed for brevity)  to
try and read out the device signature value:

avrdude -v -P /dev/cu.usbserial-A50285BI -C +ftdiprog.conf -c ftdiprog -p
t10 -U signature:r:sig.hex:h

It prints the following error (full, verbose response at end of this
message):

MOSI->MISO 0 failed

and this has me stumped.  Is this a bug, or am I doing something wrong?
Also, is there any more information about how to properly use AVRDUDE and
the TPI protocol?  This information I've found online is either rather
dated, or contradicts or other information I've read.

Thanks in advance for any help offered,

Wayne

--full response--

avrdude: Version 6.3, compiled on Sep 21 2018 at 19:15:33

         Copyright (c) 2000-2005 Brian Dean, http://www.bdmicro.com/

         Copyright (c) 2007-2014 Joerg Wunsch


         System wide configuration file is
"/usr/local/Cellar/avrdude/6.3_1/etc/avrdude.conf"

         User configuration file is "/Users/wholder/.avrduderc"

         User configuration file does not exist or is not a regular file,
skipping

         Additional configuration file is
"/var/folders/mt/7rrh06nw8xj05b0052g526300000gn/T/avr-toolchain/etc/ftdiprog.conf"


         Using Port                    : /dev/cu.usbserial-A50285BI

         Using Programmer              : ftdiprog

         AVR Part                      : ATtiny10

         Chip Erase delay              : 0 us

         PAGEL                         : P00

         BS2                           : P00

         RESET disposition             : dedicated

         RETRY pulse                   : SCK

         serial program mode           : yes

         parallel program mode         : yes

         Timeout                       : 0

         StabDelay                     : 0

         CmdexeDelay                   : 0

         SyncLoops                     : 0

         ByteDelay                     : 0

         PollIndex                     : 0

         PollValue                     : 0x00

         Memory Detail                 :


                                  Block Poll               Page
          Polled

           Memory Type Mode Delay Size  Indx Paged  Size   Size #Pages
MinW  MaxW   ReadBack

           ----------- ---- ----- ----- ---- ------ ------ ---- ------
----- ----- ---------

           signature      0     0     0    0 no          3   16      0
0     0 0x00 0x00

           fuse           0     0     4    0 no          1   16      0
0     0 0x00 0x00

           calibration    0     0     0    0 no          1   16      0
0     0 0x00 0x00

           lockbits       0     0     0    0 no          1   16      0
0     0 0x00 0x00

           flash          0     0   128    0 no       1024   16      0
0     0 0x00 0x00


         Programmer Type : SERBB

         Description     : design ftdi adatper, reset=dtr sck=tx mosi=rts
miso=cts


MOSI->MISO 0 failed

avrdude: initialization failed, rc=-1

         Double check connections and try again, or use -F to override

         this check.



avrdude done.  Thank you.