Hi all, sorry for the long delay since my last post. I was distracted by a few other things, in addition it took the German Telekom two weeks to get the upgrade of my internet connection to VDSL working. Finally I have now 50/10Mbit instead of 3/0.5Mbit , so it was  worth the trouble.  Attached to this post is a Bitstream with the working Bonfire SoC for the Papilio Pro. It boots into a monitor program, which allows some basic operation of the board. Connection speed is 500000 Baud per default. If this is a problem, I can also provide bitstreams with other default baud rates. It should print a message like this: Bonfire Boot Monitor 0.2d MIMPID: 0001000e MISA: 40001100 UART Divisor: 11 UART Revision 00000012 Uptime 0 sec SPI Flash JEDEC ID: 001720c2 The monitor supports the following commands: D <address>: dump memory, it will always dump 64 32Bit words, starting per default with address 1000000. Without entering a address the dump command will automatically dump the next 64 words X <load adr> <max size in hex>: Download a file with xmodem-crc protocol and load to <load adr>. Default load address is 100000. When no size is specified it will load the whole file in case it fits into the DRAM. Normally it is sufficent to just enter x without arguments. It has been tested to work with minicom under Linux G <address> jumps to <address> (default is again hex 1000000 when ommited, can be used to start a program downloaded with the X command E print xmodem error status. Shows the status of the last xmodem download. T test DRAM. Makes a simple (destructive) pattern test of the DRAM. When running the bitstream the first time it is best to use this command to check that everything is fine. B change baudrate. The user will be prompted for a the new baudrate. Every value between 300 and 500000 is allowed, no check further check is done, so it is possible to enter baudrates like 2423 :-) I re-display the boot message with some system info W: Write boot image. Writes the image downloaded with the X command to the flash ROM. It will write a 4KB header to flash offset 512KB, and then the image data directly behind it. The command can only be executed directly after
a X command, because it will take the size of the downloaded file to determine the size of the image. In addition the X command that the heap "sbrk" address to the first free address after the downloaded code, this address is also written to
the flash header.  R: run boot image. Will run an image written with the W command. The second attachment is a compiled binary of my eLua  (http://www.eluaproject.net/)  implementation for RISC-V (source is on https://github.com/ThomasHornschuh/elua). 
To run it, download it with the X command into RAM and start with G (both commands works with their default parameter).

  To permanently add it to flash do the following Reset the Papilio Pro with the reset button (or reload the bistream, in case you don't like to program the bitstream to flash Download with the X command Write to Flash with the W command From now on you can start eLua after boot just with "R" command >r Reading Header ...OK Boot Image found, length 339968 Bytes, Break Address: 00063b00 ...OK Heap: 00062eb0 .. 007ef7ff eLua for Bonfire SoC 1.0a __virt_timer_period 1920000 eLua v0.9_bonfire_RV32IM-7-g7996f83 Copyright (C) 2007-2013 www.eluaproject.net eLua# You can enter help to get a command help... Tipp: From the eLua# promt run: lua /rom/life.lua  for a demo of the game of live in Lua. It runs 50 iterations and prints then the runtime: ---------O---------------O------ ----------O--------------------- -----OO---------O-O------------- ----OO---------OO-OO------------ ---OO--O-OO-OOO---O-O----O------ --OO--OO-O---O------O---O-O----- ---O---OOO---O-----O----O-O----- ----OOO------O-O---------O------ -----OOO----OO-OO--------------- ------------O-O--------------OO- -------OO-------------------O--O ---------OO------------------OO- --------O--O-------------------- ---------O-O-------------O------ ----------O-------------O-O----- ------------------------O-O----- Life - generation 50, mem 22.8 kB Execution time 16.903 sec (16903.39) ms eLua#   Enjoy and please give me feedback if you like it.  Regards Thomas
      monitor.bit elua_lua_bonfire_papilio_pro.bin