I want to connect an 5" HDMI display (26 header pins) to a Raspberry Pi 3. I also want to use UART0 (Tx=GPIO14, Rx=GPIO15).
So I remapped UART 0 to Tx=GPIO36 and RX=GPIO37 by using the command in config.txt file:
dtoverlay=uart0 ,txd0_pin36,rxdo_pin=37,pin_func=7 # alt 3
I also included the following commands in rc.local:
raspi-gpio set 14 ip
raspi-gpio set 15 ip
On entering raspi-gpio get command, I am getting TXD0 and RXD0 enabled at GPIO14, GPIO15 and GPIO36, GPIO37 respectively, but still serial communication is not working. Though it was working on GPIO14, GPIO15.
Now how to enable serial communication on GPIO36, GPIO37?
Related
I have connected a new Itead sim800 board to a Raspberry Pi 4 Model B and trying to handle incoming SMS.
I have disabled the serial login shell using the link and tried gammu and minicom(with /dev/ttyAMA0, /dev/serial0 & /dev/serial1 on baud rate 9600).
But the board doesn't seem to be responding.
Following is the result of gammu.
pi#tpk:~ $ sudo gammu getallsms
No response in specified timeout. Probably the phone is not connected.
pi#tpk:~ $
Following is the result of minicom:
pi#tpk:~ $ sudo minicom -D /dev/ttyAMA0 -b 9600
Welcome to minicom 2.7.1
OPTIONS: I18n
Compiled on Aug 13 2017, 15:25:34.
Port /dev/ttyAMA0, 04:46:20
Press CTRL-A Z for help on special keys
and the console hangs without accepting any characters. The status line at the bottom shows that it's offline.
Following is the snap of the boards connected.
sim800 board on raspberry pi 4
I have a beaglebone black board. A host with 64 bit ubuntu14.04
I wanted to transfer uImage file over uart to beaglebone.
So I stopped at u-boot and type
U-Boot# loadb
## Ready for binary (kermit) download to 0x80200000 at 115200 bps...
Now it is waiting for the file. What I have to do in order to send the uImage from pc to board.
After the loadb command prints "Ready for binary download", exit from the terminal(minicom, putty etc). Note down the serial device (eg: /dev/ttyUSB0). Install kermit or its variants (eg: gkermit and ckermit are available in Ubuntu).
Assuming that /dev/ttyUSB0 is your serial device, baudrate is 115200, and no flow control is used, provide the following parameters to kermit
$kermit
kermit> set port /dev/ttyUSB0
kermit> set speed 115200
kermit> set carrier-watch off
kermit> set flow-control none
Now issue the command send , to send the file over serial line:
kermit> send filename
After the file transfer is successful, exit from kermit (use exit command), and re-open minicom. Now you can issue further commands.
NOTE : You can explicitly specify a load address to loadb. If not specified, U-boot takes load address from environment variables.
NOTE-2 : Some terminal programs have built-in facility to send files over serial line using protocols like xmodem or kermit.
This question is related to this, Cannot program ESP8266, but different settings.
I have a NodeMCU devkit v1, its comercial name is NodeMCU v2. I tried different setting to connect the devkit.
First the devkit has a usb-serial bridge (CP2102) and voltage adapter from 5v (USB) to 3.3v. So I connect the devkit with the machine via USB. The driver is installed correctly, and I can see the com, it is COM3.
After turning on the NodeMCU I can see a Wifi AI-THINKER-adfe21.
Then I tried with the nodemcu-flasher - WINDOWS.
Without any button or pin to ground. I press Flash in the flasher and stay Waiting MAC and the log says Begin Find ESP8266 as the question I told in the begin and the ESP's led (blue led) blinks.
Holding FLASH, press RESET, release FLASH. Still the same like 1.
Wire D3 (GPIO0) to GND. Same result
With ESPtool - LINUX - Trying these commands
python2 esptool.py --port /dev/ttyUSB0 read_mac
python2 esptool.py --port /dev/ttyUSB0 write_flash 0x00000 firmware.bin
Without any button or pin to ground. The output for the commands was Connecting... A fatal error occurred: Failed to connect to ESP8266
Holding FLASH, press RESET, release FLASH. Same
Wire D3 (GPIO0) to GND. Same result.
Via Arduino IDE, I installed the ESP8266 board and selected NodeMCU 1.0. The result to try upload some code -> warning: espcomm_sync failed error: espcomm_open failed
I tryed to connect the NodeMCU without the USB. Using an Arduino UNO, connecting like following... And I'm getting the same errors.
UNO | NodeMCU
5v -> Vin
GND -> GND
Rx -> Tx
Tx -> Rx
The last test I made, it is with Putty or Arduino SerialMonitor connect to the COM3 or /dev/ttyUSB0 and turning on the NodeMCU. I should see some characters or garbage if it in different baud rate. But I got nothing, the terminal is blank. I restart the NodeMCU, put it in Flash mode. No response.
Are there some solution, tip or trick to make it programmable?
PS: I know the NodeMCU is in Flash mode because its wifi disappear.
EDIT:
I discovered something.
I just connected the NodeMcu with a mobile charger and connect the D0 to Serial ground and D3 to Serial Rx. On the putty with 115200 Baudrate, I'm able to get the following code on reset.
node : sta(mac address) + softAP(mac address)
add if0
add if1
dhcp server start:(ip:192.168.4.1, mask:255.255.255.0,gw:192.168.4.1)
bcn 100
I have been working with both the node-mcu flasher and the esptool.
First in the esptool yo should use more parameter in the call. Use something like this
python esptool.py -p SERIAL_PORT_NAME --baud 9600 write_flash --flash_size=8m 0 firmware-combined.bin
Be careful with the baudrate, i always use 9600.
If you prefer using the windows program you should only connect the ESP8266 through usb and dont connect any other pin. If it still gives you problems you should check that u have installed the com ports.
Good Luck
if you are using esptool (either in Linux or windows), you should include -fm and -fs inside the esptool command. There will be no response if you did not include those 2 parameter even though it show successfully upload. you can refer the detail in this youtube tutorial or its description for flashing firmware in nodemcu V2 or v1.0.
esptool.py --port [serial-port-of-ESP8266] write_flash -fm [mode] -fs [size] 0x00000 [nodemcu-firmware].bin
Tutorial on how to flash firmware using esptool(windows):
https://www.youtube.com/watch?v=MHrm7axsImI
cheers!
Maybe you can try this setting.
$sudo esptool.py -p /dev/ttyUSB0 --baud 115200 write_flash -fs 16m -fm qio -ff 0x00000 firmware.bin
I have been trying to get my WiFi module, ESP8266 to work in the "update mode" where you connect GPIO_0 to ground.
The board is functional when GPIO_0 is disconnected from ground and I am able to use AT commands to talk to it via the Arduino serial monitor.
Following is what it prints upon connecting:
ets Jan 8 2013,rst cause:4, boot mode:(3,6)
wdt reset
load 0x40100000, len 1396, room 16
tail 4
chksum 0x89
load 0x3ffe8000, len 776, room 4
tail 4
chksum 0xe8
load 0x3ffe8308, len 540, room 4
tail 8
chksum 0xc0
csum 0xc0
2nd boot version : 1.4(b1)
SPI Speed : 40MHz
SPI Mode : DIO
SPI Flash Size & Map: 8Mbit(512KB+512KB)
jump to run user1 # 1000
rrlÌÿ
Ai-Thinker Technology Co.,Ltd.
ready
However, I cannot do most things as the firmware is out of date.
As a result, I am trying to update it (with no success)
When I set it to update mode and use the python tool "esptool.py", the script fails to connect to the ESP board.
Following is the command:
python esptool.py -p /dev/ttyUSB0 write_flash 0x00000 "/home/aditya/Desktop/v0.9.2.2 AT Firmware.bin"
Following is the output:
Connecting...
Traceback (most recent call last):
File "esptool.py", line 532, in <module>
esp.connect()
File "esptool.py", line 159, in connect
raise Exception('Failed to connect')
Exception: Failed to connect
I have even run the Windows counterpart of this tool "ESP Flasher" with no luck
The one who helps will be given a cookie (unless you value privacy)
This tool (esptool.py) works with a ROM bootloader, which is only started if GPIO_0 is tied to the GND during hardware reset. Bootloader also times out pretty fast, so just connecting GPIO_0 to the ground is not enough.
For me, following works:
Connect TXD/RXD/GND/VCC to the PC and CH_PD to VCC;
Make sure I can talk to the firmware via terminal (picocom/minicom/etc);
Connect GPIO_0 to the GND;
Connect RST to GND;
Release RST;
Run esptool.py
If still no dice, swap 5 and 6 above, i.e. first run esptool.py, then (as quickly as possible) release/disconnect RST. You will only have a second or two before esptool.py times out.
Try making the ground of all devices connected: if you have a level shifter inbetween, make sure the GND is tied to the GND of Arduino and also to the RS232 GND.
(Wow it took me a while to post this question because of the formatting problem coming from special characters..)
I'm trying to bring up virtual terminal on our embedded system's LCD usnig USB keyboard which is also connected to the system. I have UART connection to my PC so I've been using UART for console till now but I want to switch to framebuffer console on LCD during the boot at some point..
The USB host controller seems to work fine because I've seen USB memory is attached, read and written ok. And when I connect a keyboard and print the events at keyboard_event function, it prints events that seem normal and corresponding to my action(type of key, press or release..)
I have a feeling that it's a configuration problem. In init/main.c, there is
run_init_process(ramdisk_execute_command);
(In my case, ramdisk_execute_command = "/sbin/init")
And this immediately calls
kernel_execve(init_filename, argv_init, envp_init);
// above, init_filename and argv_init are "/sbin/init" same.
I expect busybox to run after this.. (ramdisk had been installed before by a bootloader-like part) but I cannot see any prints on the LCD after this point. But I can see printks on the LCD until just before calling kernel_execve above. I'm using linux 3.3.
I understand I have to open a frame buffer console on LCD and connect it to a tty but I don't know how. Below are printed the current releavant settings.
(In serial UART connection case, linux boots ok up to the final busybox shell prompt printing things in busybox initialization after kernel_execve call. and #cat /proc/fb0 returns 0 for your info. Only LCD/framebuffer console mode stops after kernel_execve.)
#### arch/sparc/boot/ourprocessor/prom_stage.c : #####
// "console=ttyS,mmio,0xff003000,115200n8 " <== serial port case
"console=tty " <= frame buffer console case (below line too)
"fbcon=font:SUN8x16,map:0000 " <= Is this boot argment correct?..
#### sbin/init: #####
#!/bin/busybox sh
export LD_LIBRARY_PATH=/lib
export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/mnt/nand/lib
exec /bin/busybox init
### rcS #####
mknod /dev/tty0 c 4 0 <== Do I need to explicitly make tty0 and tty1 like this?
mknod /dev/tty1 c 4 1
mknod /dev/tty2 c 4 2
mknod /dev/tty3 c 4 3
mknod /dev/tty4 c 4 4
### .config #####
CONFIG_FRAMEBUFFER_CONSOLE=y <= LCD/framebuffer console case. Otherwise none.
CONFIG_FONT_SUN8x16=y
CONFIG_LOGO=y
By the way, I'm not using /etc/inittab.(so use default init). The busybox init/init.c code says if there isn't the inittab file and console is not the serial port, it runs
tty2::askfirst:/bin/sh
tty3::askfirst:/bin/sh
tty4::askfirst:/bin/sh
(starting shell on tty 2, 3 and 4) then How do make tty2's shell appear on the LCD/framebuffer/framebuffer console? It's confusing and books are not so kind..
Any hint would be deeply appreciated.
This question was solved months ago and I forgot to answer to this question myself.
Adding CONFIG_FRAMEBUFFEr and CONFIG_FBCONSOLE and setting console=ttyS,.. was all that is necessary. In my case, I had another bug in DMA that was causing the frambe buffer console's text not appear on the LCD. So I can use 3 virtual consoles on the LCD (switch using Alt-F2, Alt-F3, .. ) by default. Long storyg short, console is a console(on serial port), and we have 3 (by default busybox setting) virtual console on the LCD.