nanoDLP

I tested the Build 1566 and still get an crash : "image: memory exhausted" on a raspberry pi 3. Is there a way to get previous version of nanoDLP to test?

No problem to continue in beta version! I can't go to a RAMPS because I use an home made PCB shield for raspberry pi to get direct control, fans, light,... so I wanted to continue on these setup because it's really better than a RAMPS (no firmware to update, less place, less expensive,...)

Edit : really a strange bug : I tested on a pi-zero, no crash, on a pi 3, it crash, I take the pi-zero SD card that did work and put on the pi 3, it crash. I take the SD card that crashed on a pi 3 and put it on a pi-zero, and no crash at all. I think there is a problem with arm7? (it also crash on pi 2)

Yes, it's because I said "the bug you get here" ;D
Do you have a way to remove the bug? Because my printer is just unusable and I was near to release my printer ;D

it's already on gpu_mem=128. I'm testing with 192...

Edit : same problem for 192, I'm testing with gpu_mem=256...

Edit 2 : Still get crash with gpu_mem=256 :

runtime/cgo: pthread_create failed: Resource temporarily unavailable
SIGABRT: abort
PC=0x76c3cf70 m=70 sigcode=4294967290

goroutine 0 [idle]:

goroutine 1 [IO wait]:
net.runtime_pollWait(0x74840f78, 0x72, 0x0)
    /usr/local/go/src/runtime/netpoll.go:164 +0x44
...

What to do? I build all my resin printer around a raspberry pi and custom (home made) electronic with direct control to get the smallest and simplest configuration possible but I'm facing this last issue that prevents me to go in alpha instead of bêta version ;D (everything else : meca, electronic,... are done, tested and works really great between crashes! I really like NanoDLP and would like to make it work with my setup ;D)

I tested with another SD card, same probleme, another raspberry pi, same probleme,... without the beta distribution and same probleme... I'll test tomorrow with another alimentation... It only appends when I switched to a 2K screen...

edit : the ssh connexion still work and the printer.log show this :

runtime/cgo: pthread_create failed: Resource temporarily unavailable
SIGABRT: abort
PC=0x76cedf70runtime/cgo:  m=37pthread_create failed: Resource temporarily unavailable sigcode=
4294967290

goroutine 0 [idle]:

goroutine 34 [syscall]:
runtime.notetsleepg(0x6bf05c, 0x8c895, 0x0, 0x0)
    /usr/local/go/src/runtime/lock_futex.go:205 +0x2c fp=0x10a1c794 sp=0x10a1c77c
runtime.timerproc()
    /usr/local/go/src/runtime/time.go:209 +0x464 fp=0x10a1c7ec sp=0x10a1c794
runtime.goexit()
    /usr/local/go/src/runtime/asm_arm.s:1017 +0x4 fp=0x10a1c7ec sp=0x10a1c7ec
created by runtime.addtimerLocked
    /usr/local/go/src/runtime/time.go:116 +0x124

goroutine 1 [IO wait]:
net.runtime_pollWait(0x75276f78, 0x72, 0x0)
    /usr/local/go/src/runtime/netpoll.go:164 +0x44
net.(*pollDesc).wait(0x10b32dfc, 0x72, 0x695a00, 0x10ae06c0)
    /usr/local/go/src/net/fd_poll_runtime.go:75 +0x28
net.(*pollDesc).waitRead(0x10b32dfc, 0xffffffff, 0x0)
    /usr/local/go/src/net/fd_poll_runtime.go:80 +0x24
net.(*netFD).accept(0x10b32dc0, 0x0, 0x697280, 0x10ae06c0)
    /usr/local/go/src/net/fd_unix.go:430 +0x15c
net.(*TCPListener).accept(0x10ae2048, 0x24c430, 0x10b93cbc, 0x62694)
    /usr/local/go/src/net/tcpsock_posix.go:136 +0x20
net.(*TCPListener).Accept(0x10ae2048, 0x4b7890, 0x10b2c060, 0x699f50, 0x10b1a2c0)
    /usr/local/go/src/net/tcpsock.go:228 +0x3c
net/http.(*Server).Serve(0x10a60900, 0x699708, 0x10ae2048, 0x0, 0x0)
    /usr/local/go/src/net/http/server.go:2643 +0x1ac
github.com/tylerb/graceful.(*Server).Serve(0x10a78e70, 0x699708, 0x10ae2048, 0x699708, 0x10ae2048)
    /home/pi/go/src/github.com/tylerb/graceful/graceful.go:307 +0x2c4
github.com/tylerb/graceful.(*Server).ListenAndServe(0x10a78e70, 0x4a8b50, 0x1f)
    /home/pi/go/src/github.com/tylerb/graceful/graceful.go:147 +0x78
github.com/labstack/echo.(*Echo).StartServer(0x10ac8370, 0x10a60900, 0x1, 0x10aef2fa)
    /home/pi/go/src/github.com/labstack/echo/echo.go:554 +0x35c
main.webInit()
    /home/pi/printer/app/routes.go:155 +0x3038
main.main()
    /home/pi/printer/app/server.go:79 +0x248

goroutine 17 [syscall, 86 minutes, locked to thread]:
runtime.goexit()
    /usr/local/go/src/runtime/asm_arm.s:1017 +0x4

goroutine 20 [syscall, 86 minutes]:
os/signal.signal_recv(0x0)
    /usr/local/go/src/runtime/sigqueue.go:116 +0x154
os/signal.loop()
    /usr/local/go/src/os/signal/signal_unix.go:22 +0x14
created by os/signal.init.1
    /usr/local/go/src/os/signal/signal_unix.go:28 +0x30

goroutine 21 [sleep]:
time.Sleep(0x1a55c1, 0x0)
    /usr/local/go/src/runtime/time.go:59 +0x10c
projects/printer/app/move.(*speedStruct).traditionalCalc(0x6bf2d8)
    /home/pi/go/src/projects/printer/app/move/speed.go:141 +0xc8
projects/printer/app/move.(*speedStruct).calc(0x6bf2d8, 0x10a62380)
    /home/pi/go/src/projects/printer/app/move/speed.go:95 +0x5c
created by projects/printer/app/move.init.1
    /home/pi/go/src/projects/printer/app/move/speed.go:29 +0x38

goroutine 23 [chan receive]:
main.(*StatusStruct).FindIP(0x6bf4c0)
    /home/pi/printer/app/db.go:563 +0x60
created by main.(*StatusStruct).Load
    /home/pi/printer/app/db.go:543 +0x50

goroutine 3 [chan receive]:
main.wifiStatus()
    /home/pi/printer/app/wireless.go:80 +0xf4
created by main.wifiConnect
    /home/pi/printer/app/wireless.go:23 +0xc4

goroutine 29 [sleep]:
time.Sleep(0x5f5e100, 0x0)
    /usr/local/go/src/runtime/time.go:59 +0x10c
main.(*termStruct).readLine(0x6bee68, 0x8, 0x435800, 0x10a0e018)
    /home/pi/printer/app/term.go:48 +0x2b8
main.(*termStruct).Reader(0x6bee68)
    /home/pi/printer/app/term.go:37 +0xa8
created by main.main
    /home/pi/printer/app/server.go:57 +0x134

goroutine 30 [chan receive]:
main.(*monitorStruct).watch(0x6ce510)
    /home/pi/printer/app/slice-monitor.go:46 +0x7c
created by main.main
    /home/pi/printer/app/server.go:58 +0x150

goroutine 32 [chan receive]:
projects/printer/app/hw/monitor.Monitor()
    /home/pi/go/src/projects/printer/app/hw/monitor/monitor_linux.go:33 +0x7c
created by main.main
    /home/pi/printer/app/server.go:64 +0x260

goroutine 35 [select]:
github.com/tylerb/graceful.(*Server).manageConnections(0x10a78e70, 0x10ade100, 0x10ade140, 0x10ade180, 0x10ade1c0, 0x10ade200, 0x10ade240)
    /home/pi/go/src/github.com/tylerb/graceful/graceful.go:364 +0x6a8
created by github.com/tylerb/graceful.(*Server).Serve
    /home/pi/go/src/github.com/tylerb/graceful/graceful.go:295 +0x224

goroutine 36 [select, 86 minutes, locked to thread]:
runtime.gopark(0x4b7bcc, 0x0, 0x49b50d, 0x6, 0x18, 0x2)
    /usr/local/go/src/runtime/proc.go:271 +0xfc
runtime.selectgoImpl(0x10b40fa0, 0x0, 0xc)
    /usr/local/go/src/runtime/select.go:423 +0x119c
runtime.selectgo(0x10b40fa0)
    /usr/local/go/src/runtime/select.go:238 +0x10
runtime.ensureSigM.func1()
    /usr/local/go/src/runtime/signal_unix.go:434 +0x2bc
runtime.goexit()
    /usr/local/go/src/runtime/asm_arm.s:1017 +0x4

goroutine 37 [chan receive, 86 minutes]:
github.com/tylerb/graceful.(*Server).handleInterrupt(0x10a78e70, 0x10ade280, 0x10ade380, 0x699708, 0x10ae2048)
    /home/pi/go/src/github.com/tylerb/graceful/graceful.go:419 +0x38
created by github.com/tylerb/graceful.(*Server).Serve
    /home/pi/go/src/github.com/tylerb/graceful/graceful.go:303 +0x2a4

goroutine 56 [IO wait]:
net.runtime_pollWait(0x75276c30, 0x72, 0x0)
    /usr/local/go/src/runtime/netpoll.go:164 +0x44
net.(*pollDesc).wait(0x10a1043c, 0x72, 0x0, 0x0)
    /usr/local/go/src/net/fd_poll_runtime.go:75 +0x28
net.(*pollDesc).waitRead(0x10a1043c, 0x10b9fadc, 0x400)
    /usr/local/go/src/net/fd_poll_runtime.go:80 +0x24
net.(*netFD).readFrom(0x10a10400, 0x10b9fadc, 0x400, 0x400, 0x0, 0x0, 0x0, 0x697c58, 0x695a00)
    /usr/local/go/src/net/fd_unix.go:277 +0x13c
net.(*UDPConn).readFrom(0x10a0e100, 0x10b9fadc, 0x400, 0x400, 0x4, 0x4, 0x10da3444, 0x4)
    /usr/local/go/src/net/udpsock_posix.go:47 +0x38
net.(*UDPConn).ReadFromUDP(0x10a0e100, 0x10b9fadc, 0x400, 0x400, 0x10da3400, 0x1b8, 0x0, 0x0)
    /usr/local/go/src/net/udpsock.go:97 +0x58
projects/printer/app/ssdp.Server(0x10bdcf6c, 0x2, 0x10a9df67, 0x8)
    /home/pi/go/src/projects/printer/app/ssdp/ssdp.go:57 +0x164
created by main.afterIP
    /home/pi/printer/app/server.go:101 +0x8c

goroutine 58 [sleep]:
time.Sleep(0xf8475800, 0xd)
    /usr/local/go/src/runtime/time.go:59 +0x10c
main.updateControlPanel()
    /home/pi/printer/app/server.go:201 +0x28
created by main.afterIP
    /home/pi/printer/app/server.go:103 +0xe8

goroutine 15 [IO wait]:
net.runtime_pollWait(0x75276ca8, 0x72, 0x10b58000)
    /usr/local/go/src/runtime/netpoll.go:164 +0x44
net.(*pollDesc).wait(0x10a621bc, 0x72, 0x697c58, 0x695a00)
    /usr/local/go/src/net/fd_poll_runtime.go:75 +0x28
net.(*pollDesc).waitRead(0x10a621bc, 0x10b58000, 0x1000)
    /usr/local/go/src/net/fd_poll_runtime.go:80 +0x24
net.(*netFD).Read(0x10a62180, 0x10b58000, 0x1000, 0x1000, 0x0, 0x697c58, 0x695a00)
    /usr/local/go/src/net/fd_unix.go:250 +0x148
net.(*conn).Read(0x10a66520, 0x10b58000, 0x1000, 0x1000, 0x0, 0x0, 0x0)
    /usr/local/go/src/net/net.go:181 +0x58
net/http.(*connReader).Read(0x10a64360, 0x10b58000, 0x1000, 0x1000, 0x248f74, 0x10a62180, 0xd0f60cae)
    /usr/local/go/src/net/http/server.go:754 +0x168
bufio.(*Reader).fill(0x10ad2810)
    /usr/local/go/src/bufio/bufio.go:97 +0xf4
bufio.(*Reader).Peek(0x10ad2810, 0x4, 0xe, 0x310487d1, 0x6bf198, 0x0, 0x0)
    /usr/local/go/src/bufio/bufio.go:129 +0x58
net/http.(*conn).serve(0x10a985a0, 0x699ed8, 0x10a14160)
    /usr/local/go/src/net/http/server.go:1850 +0x7a0
created by net/http.(*Server).Serve
    /usr/local/go/src/net/http/server.go:2668 +0x234

goroutine 103 [IO wait]:
net.runtime_pollWait(0x75276d20, 0x72, 0x10c2b000)
    /usr/local/go/src/runtime/netpoll.go:164 +0x44
net.(*pollDesc).wait(0x10b333bc, 0x72, 0x697c58, 0x695a00)
    /usr/local/go/src/net/fd_poll_runtime.go:75 +0x28
net.(*pollDesc).waitRead(0x10b333bc, 0x10c2b000, 0x1000)
    /usr/local/go/src/net/fd_poll_runtime.go:80 +0x24
net.(*netFD).Read(0x10b33380, 0x10c2b000, 0x1000, 0x1000, 0x0, 0x697c58, 0x695a00)
    /usr/local/go/src/net/fd_unix.go:250 +0x148
net.(*conn).Read(0x10cafc70, 0x10c2b000, 0x1000, 0x1000, 0x0, 0x0, 0x0)
    /usr/local/go/src/net/net.go:181 +0x58
net/http.(*connReader).Read(0x10c635f0, 0x10c2b000, 0x1000, 0x1000, 0x248f74, 0x10b33380, 0xd0f60cae)
    /usr/local/go/src/net/http/server.go:754 +0x168
bufio.(*Reader).fill(0x10c63620)
    /usr/local/go/src/bufio/bufio.go:97 +0xf4
bufio.(*Reader).Peek(0x10c63620, 0x4, 0xe, 0x310a9da1, 0x6bf198, 0x0, 0x0)
    /usr/local/go/src/bufio/bufio.go:129 +0x58
net/http.(*conn).serve(0x10d5ef00, 0x699ed8, 0x10dfc340)
    /usr/local/go/src/net/http/server.go:1850 +0x7a0
created by net/http.(*Server).Serve
    /usr/local/go/src/net/http/server.go:2668 +0x234

goroutine 3664 [runnable]:
time.Sleep(0xd207f, 0x0)
    /usr/local/go/src/runtime/time.go:59 +0x10c
projects/printer/app/move.ZAxisMove(0x960, 0x1e501, 0x1fca05, 0x0, 0x1fca05, 0x0, 0x160f, 0x4b7714, 0x0, 0x0, ...)
    /home/pi/go/src/projects/printer/app/move/move.go:60 +0x4fc
main.gpioInterface(0x960, 0x6bf501, 0x12c, 0x0, 0x3b5500, 0x6bf520)
    /home/pi/printer/app/move.go:106 +0x53c
main.rise(0x960, 0x12c, 0x0, 0x6bf400, 0xf6)
    /home/pi/printer/app/move.go:59 +0x3c
main.riseMicron(0xbb8, 0x12c, 0x0, 0x0, 0x3cc5d0)
    /home/pi/printer/app/move.go:63 +0x8c
main.moveToWaitPosition()
    /home/pi/printer/app/move.go:44 +0x98
main.printLayer(0xf6, 0xf7)
    /home/pi/printer/app/printing.go:236 +0x560
main.startPlate(0x2, 0x1)
    /home/pi/printer/app/printing.go:96 +0x1a4
created by main.printerStart
    /home/pi/printer/app/web.go:660 +0x118

trap    0x0
error   0x0
oldmask 0x0
r0      0x0
r1      0x7e9
r2      0x6
r3      0x0
r4      0x76dfe094
r5      0x629ff460
r6      0x0
r7      0x10c
r8      0x1
r9      0x34
r10     0x10ec24b0
fp      0x629fec04
ip      0x629ff920
sp      0x629fead0
lr      0x76cedf44
pc      0x76cedf70
cpsr    0x20000010
fault   0x0

Ok, I'll try on another SD card, new installation,... It's possible because I reinstalled everything friday and never get this problem before.

Hello,

I tried the NanoDLP mac version, I was searching about infill in nanoSlicer and I see a nano dlp mac version today ;D
Unfortunately, it works only for a few page : if I go to the setup page, it stop working, same in import profile,... Is there a way to start it in debug mode ?

edit : too bad for NanoSlicer support, I was planning create a desktop app to slice stl throught nanoslicer. Nano DLP is really great but not so user frendly for newbies and my plan would be to get it user flendly, with touch screen (already working), full worklow with auto-orient,... on a desktop app (based on Electron) whith nanoslicer cli,... it only miss infill ;D

I think it's a better debug files here : https://we.tl/K89BodqrQw

I run a 1h print and everything work great. I run juste after a 4h print and after 31 layer, it crash. There is a lot of crash line in the printer.log file

Hello I have the same problem on a raspberry pi 2.

Here are the last log :

2017/07/08 19:24:37.943073 {"Layer":"193","module":"GPIO","level":"Notice","msg":"Set Pin 19 to True"}
2017/07/08 19:24:38.042493 {"Layer":"193","module":"Image","level":"Warning","msg":"Display layer public/plates/3/193.png"}
image: memory exhausted

I print with a 2K 5"5 screen. It crash on every print with this problem.

Hello, I tried the mac version but the only things I get is "{
message: "Internal Server Error"
}" on my browser.
(event if I run it with "sudo")

need help ;D

I tested a D7 SD card image and have exactly the same problem. Like my setup, it works fine when the screen is in portrait mode. But the problem is : the orientation of the screen and so the build plate is in portrait mode. Every printer (fdm, sla,...) are in landscape mode. Here, the setup in portrait mode is a probleme because every STL must be configurate in portrait mode to and not in landscape like every printer to fit in the buildplate. So a image rotation would be greate to get a landscape screen and an easy setep when using meshmixer,...

here is the debug info if I insert display_rotate=3 in the config :

SIGABRT: abort
PC=0xb6cbbf70 m=0 sigcode=4294967290

goroutine 0 [idle]:

goroutine 1 [IO wait, 1 minutes]:
net.runtime_pollWait(0xb5a89120, 0x72, 0x0)
    /usr/local/go/src/runtime/netpoll.go:164 +0x44
net.(*pollDesc).wait(0x10ae6e3c, 0x72, 0x695a00, 0x10dd4d90)
    /usr/local/go/src/net/fd_poll_runtime.go:75 +0x28
net.(*pollDesc).waitRead(0x10ae6e3c, 0xffffffff, 0x0)
    /usr/local/go/src/net/fd_poll_runtime.go:80 +0x24
net.(*netFD).accept(0x10ae6e00, 0x0, 0x697280, 0x10dd4d90)
    /usr/local/go/src/net/fd_unix.go:430 +0x15c
net.(*TCPListener).accept(0x10a0f230, 0x24c430, 0x10a3fcbc, 0x62694)
    /usr/local/go/src/net/tcpsock_posix.go:136 +0x20
net.(*TCPListener).Accept(0x10a0f230, 0x4b7890, 0x10cf3500, 0x699f50, 0x10ae1aa0)
    /usr/local/go/src/net/tcpsock.go:228 +0x3c
net/http.(*Server).Serve(0x10a0ab00, 0x699708, 0x10a0f230, 0x0, 0x0)
    /usr/local/go/src/net/http/server.go:2643 +0x1ac
github.com/tylerb/graceful.(*Server).Serve(0x10a4ecb0, 0x699708, 0x10a0f230, 0x699708, 0x10a0f230)
    /home/pi/go/src/github.com/tylerb/graceful/graceful.go:307 +0x2c4
github.com/tylerb/graceful.(*Server).ListenAndServe(0x10a4ecb0, 0x4a8b50, 0x1f)
    /home/pi/go/src/github.com/tylerb/graceful/graceful.go:147 +0x78
github.com/labstack/echo.(*Echo).StartServer(0x10aa6420, 0x10a0ab00, 0x1, 0x10ac53aa)
    /home/pi/go/src/github.com/labstack/echo/echo.go:554 +0x35c
main.webInit()
    /home/pi/printer/app/routes.go:155 +0x3038
main.main()
    /home/pi/printer/app/server.go:79 +0x248

goroutine 17 [syscall, 1 minutes, locked to thread]:
runtime.goexit()
    /usr/local/go/src/runtime/asm_arm.s:1017 +0x4

goroutine 5 [syscall, 1 minutes]:
os/signal.signal_recv(0x0)
    /usr/local/go/src/runtime/sigqueue.go:116 +0x154
os/signal.loop()
    /usr/local/go/src/os/signal/signal_unix.go:22 +0x14
created by os/signal.init.1
    /usr/local/go/src/os/signal/signal_unix.go:28 +0x30

goroutine 6 [chan receive, 1 minutes]:
projects/printer/app/move.(*speedStruct).calc(0x6bf2d8, 0x10a103c0)
    /home/pi/go/src/projects/printer/app/move/speed.go:92 +0x2c
created by projects/printer/app/move.init.1
    /home/pi/go/src/projects/printer/app/move/speed.go:29 +0x38

goroutine 49 [IO wait, 1 minutes]:
net.runtime_pollWait(0xb5a88ec8, 0x72, 0x10e07000)
    /usr/local/go/src/runtime/netpoll.go:164 +0x44
net.(*pollDesc).wait(0x10ddf73c, 0x72, 0x697c58, 0x695a00)
    /usr/local/go/src/net/fd_poll_runtime.go:75 +0x28
net.(*pollDesc).waitRead(0x10ddf73c, 0x10e07000, 0x1000)
    /usr/local/go/src/net/fd_poll_runtime.go:80 +0x24
net.(*netFD).Read(0x10ddf700, 0x10e07000, 0x1000, 0x1000, 0x0, 0x697c58, 0x695a00)
    /usr/local/go/src/net/fd_unix.go:250 +0x148
net.(*conn).Read(0x10d0bc58, 0x10e07000, 0x1000, 0x1000, 0x0, 0x0, 0x0)
    /usr/local/go/src/net/net.go:181 +0x58
net/http.(*connReader).Read(0x10e007e0, 0x10e07000, 0x1000, 0x1000, 0x248f74, 0x10ddf700, 0xd0e76c9a)
    /usr/local/go/src/net/http/server.go:754 +0x168
bufio.(*Reader).fill(0x10e00810)
    /usr/local/go/src/bufio/bufio.go:97 +0xf4
bufio.(*Reader).Peek(0x10e00810, 0x4, 0xe, 0x15cf57f0, 0x6bf198, 0x0, 0x0)
    /usr/local/go/src/bufio/bufio.go:129 +0x58
net/http.(*conn).serve(0x10cf3380, 0x699ed8, 0x10df1180)
    /usr/local/go/src/net/http/server.go:1850 +0x7a0
created by net/http.(*Server).Serve
    /usr/local/go/src/net/http/server.go:2668 +0x234

goroutine 8 [chan receive]:
main.(*StatusStruct).FindIP(0x6bf4c0)
    /home/pi/printer/app/db.go:563 +0x60
created by main.(*StatusStruct).Load
    /home/pi/printer/app/db.go:543 +0x50

goroutine 29 [sleep, 1 minutes]:
time.Sleep(0xe11d6000, 0x37)
    /usr/local/go/src/runtime/time.go:59 +0x10c
main.updateControlPanel()
    /home/pi/printer/app/server.go:203 +0x54
created by main.afterIP
    /home/pi/printer/app/server.go:103 +0xe8

goroutine 46 [IO wait, 1 minutes]:
net.runtime_pollWait(0xb5a88fb8, 0x72, 0x10deb000)
    /usr/local/go/src/runtime/netpoll.go:164 +0x44
net.(*pollDesc).wait(0x10dde8fc, 0x72, 0x697c58, 0x695a00)
    /usr/local/go/src/net/fd_poll_runtime.go:75 +0x28
net.(*pollDesc).waitRead(0x10dde8fc, 0x10deb000, 0x1000)
    /usr/local/go/src/net/fd_poll_runtime.go:80 +0x24
net.(*netFD).Read(0x10dde8c0, 0x10deb000, 0x1000, 0x1000, 0x0, 0x697c58, 0x695a00)
    /usr/local/go/src/net/fd_unix.go:250 +0x148
net.(*conn).Read(0x10d0bb68, 0x10deb000, 0x1000, 0x1000, 0x0, 0x0, 0x0)
    /usr/local/go/src/net/net.go:181 +0x58
net/http.(*connReader).Read(0x10daf2f0, 0x10deb000, 0x1000, 0x1000, 0x248f74, 0x10dde8c0, 0xd0e76c5d)
    /usr/local/go/src/net/http/server.go:754 +0x168
bufio.(*Reader).fill(0x10daf320)
    /usr/local/go/src/bufio/bufio.go:97 +0xf4
bufio.(*Reader).Peek(0x10daf320, 0x4, 0xe, 0x215470b0, 0x6bf198, 0x0, 0x0)
    /usr/local/go/src/bufio/bufio.go:129 +0x58
net/http.(*conn).serve(0x10cf3140, 0x699ed8, 0x10dd17c0)
    /usr/local/go/src/net/http/server.go:1850 +0x7a0
created by net/http.(*Server).Serve
    /usr/local/go/src/net/http/server.go:2668 +0x234

goroutine 48 [IO wait]:
net.runtime_pollWait(0xb5a88f40, 0x72, 0x10e03000)
    /usr/local/go/src/runtime/netpoll.go:164 +0x44
net.(*pollDesc).wait(0x10ddf63c, 0x72, 0x697c58, 0x695a00)
    /usr/local/go/src/net/fd_poll_runtime.go:75 +0x28
net.(*pollDesc).waitRead(0x10ddf63c, 0x10e03000, 0x1000)
    /usr/local/go/src/net/fd_poll_runtime.go:80 +0x24
net.(*netFD).Read(0x10ddf600, 0x10e03000, 0x1000, 0x1000, 0x0, 0x697c58, 0x695a00)
    /usr/local/go/src/net/fd_unix.go:250 +0x148
net.(*conn).Read(0x10d0bc48, 0x10e03000, 0x1000, 0x1000, 0x0, 0x0, 0x0)
    /usr/local/go/src/net/net.go:181 +0x58
net/http.(*connReader).Read(0x10e00780, 0x10e03000, 0x1000, 0x1000, 0x248f74, 0x10ddf600, 0xd0e76cb4)
    /usr/local/go/src/net/http/server.go:754 +0x168
bufio.(*Reader).fill(0x10e007b0)
    /usr/local/go/src/bufio/bufio.go:97 +0xf4
bufio.(*Reader).Peek(0x10e007b0, 0x4, 0xe, 0x1d316b50, 0x6bf198, 0x0, 0x0)
    /usr/local/go/src/bufio/bufio.go:129 +0x58
net/http.(*conn).serve(0x10cf3320, 0x699ed8, 0x10df10c0)
    /usr/local/go/src/net/http/server.go:1850 +0x7a0
created by net/http.(*Server).Serve
    /usr/local/go/src/net/http/server.go:2668 +0x234

goroutine 26 [chan receive]:
main.wifiStatus()
    /home/pi/printer/app/wireless.go:80 +0xf4
created by main.wifiConnect
    /home/pi/printer/app/wireless.go:23 +0xc4

goroutine 15 [runnable]:
time.Sleep(0x5f5e100, 0x0)
    /usr/local/go/src/runtime/time.go:59 +0x10c
main.(*termStruct).readLine(0x6bee68, 0x8, 0x435800, 0x10a0f2b0)
    /home/pi/printer/app/term.go:48 +0x2b8
main.(*termStruct).Reader(0x6bee68)
    /home/pi/printer/app/term.go:37 +0xa8
created by main.main
    /home/pi/printer/app/server.go:57 +0x134

goroutine 16 [chan receive]:
main.(*monitorStruct).watch(0x6ce510)
    /home/pi/printer/app/slice-monitor.go:46 +0x7c
created by main.main
    /home/pi/printer/app/server.go:58 +0x150

goroutine 19 [chan receive]:
projects/printer/app/hw/monitor.Monitor()
    /home/pi/go/src/projects/printer/app/hw/monitor/monitor_linux.go:33 +0x7c
created by main.main
    /home/pi/printer/app/server.go:64 +0x260

goroutine 27 [IO wait]:
net.runtime_pollWait(0xb5a890a8, 0x72, 0x0)
    /usr/local/go/src/runtime/netpoll.go:164 +0x44
net.(*pollDesc).wait(0x10ae78fc, 0x72, 0x0, 0x0)
    /usr/local/go/src/net/fd_poll_runtime.go:75 +0x28
net.(*pollDesc).waitRead(0x10ae78fc, 0x10a2cadc, 0x400)
    /usr/local/go/src/net/fd_poll_runtime.go:80 +0x24
net.(*netFD).readFrom(0x10ae78c0, 0x10a2cadc, 0x400, 0x400, 0x0, 0x0, 0x0, 0x697c58, 0x695a00)
    /usr/local/go/src/net/fd_unix.go:277 +0x13c
net.(*UDPConn).readFrom(0x10a0f450, 0x10a2cadc, 0x400, 0x400, 0x4, 0x4, 0x10bd62a4, 0x4)
    /usr/local/go/src/net/udpsock_posix.go:47 +0x38
net.(*UDPConn).ReadFromUDP(0x10a0f450, 0x10a2cadc, 0x400, 0x400, 0x10bd6200, 0xdc, 0x0, 0x0)
    /usr/local/go/src/net/udpsock.go:97 +0x58
projects/printer/app/ssdp.Server(0x10ac5930, 0x2, 0x10aca11d, 0x8)
    /home/pi/go/src/projects/printer/app/ssdp/ssdp.go:57 +0x164
created by main.afterIP
    /home/pi/printer/app/server.go:101 +0x8c

goroutine 22 [select]:
github.com/tylerb/graceful.(*Server).manageConnections(0x10a4ecb0, 0x10ae6f00, 0x10ae6f40, 0x10ae6f80, 0x10ae6fc0, 0x10ae7000, 0x10ae7040)
    /home/pi/go/src/github.com/tylerb/graceful/graceful.go:364 +0x6a8
created by github.com/tylerb/graceful.(*Server).Serve
    /home/pi/go/src/github.com/tylerb/graceful/graceful.go:295 +0x224

goroutine 23 [select, 1 minutes, locked to thread]:
runtime.gopark(0x4b7bcc, 0x0, 0x49b50d, 0x6, 0x18, 0x2)
    /usr/local/go/src/runtime/proc.go:271 +0xfc
runtime.selectgoImpl(0x10addfa0, 0x0, 0xc)
    /usr/local/go/src/runtime/select.go:423 +0x119c
runtime.selectgo(0x10addfa0)
    /usr/local/go/src/runtime/select.go:238 +0x10
runtime.ensureSigM.func1()
    /usr/local/go/src/runtime/signal_unix.go:434 +0x2bc
runtime.goexit()
    /usr/local/go/src/runtime/asm_arm.s:1017 +0x4

goroutine 24 [chan receive, 1 minutes]:
github.com/tylerb/graceful.(*Server).handleInterrupt(0x10a4ecb0, 0x10ae7080, 0x10ae7180, 0x699708, 0x10a0f230)
    /home/pi/go/src/github.com/tylerb/graceful/graceful.go:419 +0x38
created by github.com/tylerb/graceful.(*Server).Serve
    /home/pi/go/src/github.com/tylerb/graceful/graceful.go:303 +0x2a4

goroutine 44 [IO wait, 1 minutes]:
net.runtime_pollWait(0xb5a89030, 0x72, 0x10dc3000)
    /usr/local/go/src/runtime/netpoll.go:164 +0x44
net.(*pollDesc).wait(0x10d8dabc, 0x72, 0x697c58, 0x695a00)
    /usr/local/go/src/net/fd_poll_runtime.go:75 +0x28
net.(*pollDesc).waitRead(0x10d8dabc, 0x10dc3000, 0x1000)
    /usr/local/go/src/net/fd_poll_runtime.go:80 +0x24
net.(*netFD).Read(0x10d8da80, 0x10dc3000, 0x1000, 0x1000, 0x0, 0x697c58, 0x695a00)
    /usr/local/go/src/net/fd_unix.go:250 +0x148
net.(*conn).Read(0x10d0b9e0, 0x10dc3000, 0x1000, 0x1000, 0x0, 0x0, 0x0)
    /usr/local/go/src/net/net.go:181 +0x58
net/http.(*connReader).Read(0x10dae7e0, 0x10dc3000, 0x1000, 0x1000, 0x248f74, 0x10d8da80, 0xd0e76c98)
    /usr/local/go/src/net/http/server.go:754 +0x168
bufio.(*Reader).fill(0x10dae810)
    /usr/local/go/src/bufio/bufio.go:97 +0xf4
bufio.(*Reader).Peek(0x10dae810, 0x4, 0xe, 0x20e64978, 0x6bf198, 0x0, 0x0)
    /usr/local/go/src/bufio/bufio.go:129 +0x58
net/http.(*conn).serve(0x10cf2f60, 0x699ed8, 0x10db96a0)
    /usr/local/go/src/net/http/server.go:1850 +0x7a0
created by net/http.(*Server).Serve
    /usr/local/go/src/net/http/server.go:2668 +0x234

trap    0x0
error   0x0
oldmask 0x4000
r0      0x0
r1      0x2ae
r2      0x6
r3      0x0
r4      0xb6dcc094
r5      0xb6f76420
r6      0x0
r7      0x10c
r8      0x1
r9      0xff
r10     0x6bf760
fp      0x0
ip      0xb6f768e0
sp      0xbea8f6f8
lr      0xb6cbbf44
pc      0xb6cbbf70
cpsr    0x20000010
fault   0x0

Ok, but how? for exemple : http://127.0.0.1:8080/shutter/open of printer/stop,... how can I can get json response instead of html?