Category: lua

STM32F4Discovery + eLua + OSX

by Tom

I fixed few bugs when compiling elua from git on osx – clone my branch clone official repo here.

$ ./build_elua.lua board=stm32f4discovery

create .bin file

$ arm-none-eabi-objcopy -O binary elua_lua_stm32f4discovery.elf elua_lua_stm32f4discovery.bin

create openocd config file for stm32f4 board:

$ cat ~/stm32f4discovery.cfg
# stm32f4discover board
source [find interface/stlink-v2-1.cfg]
transport select hla_swd
source [find target/stm32f4x.cfg]
reset_config srst_only

and upload to the board:

$ openocd -f ~/stm32f4discovery.cfg \
   -c "init" \   
   -c "reset halt" \
   -c "sleep 100" \
   -c "wait_halt 2" 
   -c "echo \"--- Writing elua_lua_stm32f4discovery.bin\"" \
   -c "flash write_image erase elua_lua_stm32f4discovery.bin 0x08000000" \
   -c "sleep 100" \
   -c "echo \"--- Verifying\"" \
   -c "verify_image elua_lua_stm32f4discovery.bin 0x08000000" \
   -c "sleep 100" \
   -c "echo \"--- Done\"" \
   -c "resume" \
   -c "shutdown"

Open On-Chip Debugger 0.9.0 (2015-11-16-01:48)
Licensed under GNU GPL v2
For bug reports, read
	http://openocd.org/doc/doxygen/bugs.html
Info : The selected transport took over low-level target control. The results might differ compared to plain JTAG/SWD
adapter speed: 2000 kHz
adapter_nsrst_delay: 100
none separate
srst_only separate srst_nogate srst_open_drain connect_deassert_srst
Info : Unable to match requested speed 2000 kHz, using 1800 kHz
Info : Unable to match requested speed 2000 kHz, using 1800 kHz
Info : clock speed 1800 kHz
Info : STLINK v2 JTAG v25 API v2 SWIM v14 VID 0x0483 PID 0x374B
Info : using stlink api v2
Info : Target voltage: 2.884520
Info : stm32f4x.cpu: hardware has 6 breakpoints, 4 watchpoints
target state: halted
target halted due to debug-request, current mode: Thread
xPSR: 0x01000000 pc: 0x080063f0 msp: 0x20000c78
--- Writing elua_lua_stm32f4discovery.bin
auto erase enabled
Info : device id = 0x10076413
Info : flash size = 1024kbytes
wrote 262144 bytes from file elua_lua_stm32f4discovery.bin in 7.783807s (32.889 KiB/s)
--- Verifying
target state: halted
target halted due to breakpoint, current mode: Thread
xPSR: 0x61000000 pc: 0x2000002e msp: 0x20000c78
verified 220776 bytes in 2.229936s (96.685 KiB/s)
--- Done
shutdown command invoked

Now you can connect to the board using /dev/tty.usbmodem621, 115200/8/n/1. You should get this prompt:

eLua#
eLua# help
Shell commands:
  help   - shell help
  lua    - start a Lua session
  ls     - lists files and directories
  dir    - lists files and directories
  cat    - list the contents of a file
  type   - list the contents of a file
  recv   - receive files via XMODEM
  cp     - copy files
  mv     - move/rename files
  rm     - remove files
  ver    - show version information
  mkdir  - create directories
  exit   - exit the shell
For more information use 'help <command>'.
eLua# lua
Press CTRL+Z to exit Lua
Lua 5.1.4  Copyright (C) 1994-2011 Lua.org, PUC-Rio
> print(pd.board() .. "/" .. pd.platform() .. "/" .. pd.cpu())
STM32F4DISCOVERY/STM32F4/STM32F407VG

enjoy :)

nodemcu – simple webserver

by Tom

I’ve modified and updated this source:

local SSID = "my_wifi_ssid"
local SSID_PASSWORD = "my_wifi_password"

local function http_header(conn)
  conn:send('HTTP/1.1 200 OK\n\n')
  conn:send('<!DOCTYPE HTML>\n')
  conn:send('<html>\n')
  conn:send('<head><meta  content="text/html; charset=utf-8">\n')
  conn:send('<title>ESP8266 znouza test</title></head>\n')
end

local function connect (conn, data)
   local query_data

   conn:on ("receive",
      function (cn, req_data)
         query_data = get_http_req (req_data)
         print (query_data["METHOD"] .. " " .. " " .. query_data["User-Agent"])
         http_header(cn)
         cn:send ("<body>")
         cn:send ("<h1>Hello World from ESP8266 and NodeMCU!!</h1>")
         cn:send ("</body></html>")
         -- Close the connection for the request
         cn:close ( )
      end)
end

function wait_for_wifi_conn ( )
   tmr.alarm (1, 1000, 1, function ( )
      if wifi.sta.getip ( ) == nil then
         print ("Waiting for Wifi connection")
      else
         tmr.stop (1)
         print ("ESP8266 mode is: " .. wifi.getmode ( ))
         print ("The module MAC address is: " .. wifi.sta.getmac ( ))
         print ("Config done, IP is " .. wifi.sta.getip ( ))
      end
   end)
end

-- Build and return a table of the http request data
function get_http_req (instr)
   local t = {}
   local first = nil
   local key, v, strt_ndx, end_ndx

   for str in string.gmatch (instr, "([^\n]+)") do
      -- First line in the method and path
      if (first == nil) then
         first = 1
         strt_ndx, end_ndx = string.find (str, "([^ ]+)")
         v = trim (string.sub (str, end_ndx + 2))
         key = trim (string.sub (str, strt_ndx, end_ndx))
         t["METHOD"] = key
         t["REQUEST"] = v
      else -- Process and remaining ":" fields
         strt_ndx, end_ndx = string.find (str, "([^:]+)")
         if (end_ndx ~= nil) then
            v = trim (string.sub (str, end_ndx + 2))
            key = trim (string.sub (str, strt_ndx, end_ndx))
            t[key] = v
         end
      end
   end

   return t
end

-- String trim left and right
function trim (s)
  return (s:gsub ("^%s*(.-)%s*$", "%1"))
end

-- Configure the ESP as a station (client)
wifi.setmode (wifi.STATION)
wifi.sta.config (SSID, SSID_PASSWORD,1)

-- Hang out until we get a wifi connection before the httpd server is started.
wait_for_wifi_conn ( )

-- Create the httpd server
svr = net.createServer (net.TCP, 30)

-- Server listening on port 80, call connect function if a request is received
svr:listen (80, connect)

nodemcu + el capitan

by Tom

To flash

git clone https://github.com/themadinventor/esptool.git 
cd esptool
sudo python ./setup.py install
  • upgrade firmware
$ python ./esptool.py --port=/dev/cu.wchusbserial620  write_flash  -fm=dio -fs=32m 0x00000 /tmp/nodemcu_integer_0.9.6-dev_20150704.bin

Connecting...
Erasing flash...
Took 3.92s to erase flash block
Wrote 450560 bytes at 0x00000000 in 54.1 seconds (66.6 kbit/s)...

Leaving...