Acessando a console serial na Beaglebone Black
- por Sergio Prado
A Beaglebone Black possui uma porta serial configurada como console que pode ser acessada através do barramento de pinos J1, conforme figura abaixo:
A pinagem é a seguinte:
- Pino 1: Terra
- Pino 4: RX
- Pino 5: TX
Para a conexão, você vai precisar de um cabo conversor FTDI para TTL de 3,3V, que pode ser adquirido facilmente em lojas como a Digikey ou Sparkfun.
Então é só conectar o cabo e configurar sua aplicação de terminal favorita (minicom, picocom, screen, etc) em 115200,8N1 e testar.
Você deverá visualizar as mensagens de boot do kernel e terá acesso ao sistema operacional.
U-Boot SPL 2013.04-dirty (Jun 19 2013 - 09:57:14) musb-hdrc: ConfigData=0xde (UTMI-8, dyn FIFOs, HB-ISO Rx, HB-ISO Tx, SoftConn) musb-hdrc: MHDRC RTL version 2.0 musb-hdrc: setup fifo_mode 4 musb-hdrc: 28/31 max ep, 16384/16384 memory USB Peripheral mode controller at 47401000 using PIO, IRQ 0 musb-hdrc: ConfigData=0xde (UTMI-8, dyn FIFOs, HB-ISO Rx, HB-ISO Tx, SoftConn) musb-hdrc: MHDRC RTL version 2.0 musb-hdrc: setup fifo_mode 4 musb-hdrc: 28/31 max ep, 16384/16384 memory USB Host mode controller at 47401800 using PIO, IRQ 0 OMAP SD/MMC: 0 mmc_send_cmd : timeout: No status update reading u-boot.img reading u-boot.img U-Boot 2013.04-dirty (Jun 19 2013 - 09:57:14) I2C: ready DRAM: 512 MiB WARNING: Caches not enabled NAND: No NAND device found!!! 0 MiB MMC: OMAP SD/MMC: 0, OMAP SD/MMC: 1 *** Warning - readenv() failed, using default environment musb-hdrc: ConfigData=0xde (UTMI-8, dyn FIFOs, HB-ISO Rx, HB-ISO Tx, SoftConn) musb-hdrc: MHDRC RTL version 2.0 musb-hdrc: setup fifo_mode 4 musb-hdrc: 28/31 max ep, 16384/16384 memory USB Peripheral mode controller at 47401000 using PIO, IRQ 0 musb-hdrc: ConfigData=0xde (UTMI-8, dyn FIFOs, HB-ISO Rx, HB-ISO Tx, SoftConn) musb-hdrc: MHDRC RTL version 2.0 musb-hdrc: setup fifo_mode 4 musb-hdrc: 28/31 max ep, 16384/16384 memory USB Host mode controller at 47401800 using PIO, IRQ 0 Net: not set. Validating first E-fuse MAC cpsw, usb_ether Hit any key to stop autoboot: 0 gpio: pin 53 (gpio 53) value is 1 Card did not respond to voltage select! mmc0(part 0) is current device mmc_send_cmd : timeout: No status update Card did not respond to voltage select! No micro SD card found, setting mmcdev to 1 mmc_send_cmd : timeout: No status update mmc1(part 0) is current device gpio: pin 54 (gpio 54) value is 1 SD/MMC found on device 1 reading uEnv.txt 26 bytes read in 3 ms (7.8 KiB/s) Loaded environment from uEnv.txt Importing environment from mmc ... gpio: pin 55 (gpio 55) value is 1 4270840 bytes read in 746 ms (5.5 MiB/s) gpio: pin 56 (gpio 56) value is 1 24129 bytes read in 51 ms (461.9 KiB/s) Booting from mmc ... ## Booting kernel from Legacy Image at 80007fc0 ... Image Name: Angstrom/3.8.13/beaglebone Image Type: ARM Linux Kernel Image (uncompressed) Data Size: 4270776 Bytes = 4.1 MiB Load Address: 80008000 Entry Point: 80008000 Verifying Checksum ... OK ## Flattened Device Tree blob at 80f80000 Booting using the fdt blob at 0x80f80000 XIP Kernel Image ... OK OK Using Device Tree in place at 80f80000, end 80f88e40 Starting kernel ... Uncompressing Linux... done, booting the kernel. [ 0.194102] omap2_mbox_probe: platform not supported [ 0.204676] tps65217-bl tps65217-bl: no platform data provided [ 0.281263] bone-capemgr bone_capemgr.8: slot #0: No cape found [ 0.318368] bone-capemgr bone_capemgr.8: slot #1: No cape found [ 0.355477] bone-capemgr bone_capemgr.8: slot #2: No cape found [ 0.392586] bone-capemgr bone_capemgr.8: slot #3: No cape found [ 0.412613] bone-capemgr bone_capemgr.8: slot #6: BB-BONELT-HDMIN conflict P8.45 (#5:BB-BONELT-HDMI) [ 0.422233] bone-capemgr bone_capemgr.8: slot #6: Failed verification [ 0.429009] bone-capemgr bone_capemgr.8: loader: failed to load slot-6 BB-BONELT-HDMIN:00A0 (prio 2) [ 0.451649] omap_hsmmc mmc.4: of_parse_phandle_with_args of 'reset' failed [ 0.516109] pinctrl-single 44e10800.pinmux: pin 44e10854 already requested by 44e10800.pinmux; cannot claim for gpio-leds.7 [ 0.527848] pinctrl-single 44e10800.pinmux: pin-21 (gpio-leds.7) status -22 [ 0.535163] pinctrl-single 44e10800.pinmux: could not request pin 21 on device pinctrl-single systemd-fsck[84]: Angstrom: clean, 50618/112672 files, 288145/449820 blocks [ 6.389314] libphy: PHY 4a101000.mdio:01 not found [ 6.394363] net eth0: phy 4a101000.mdio:01 not found on slave 1 .---O---. | | .-. o o | | |-----.-----.-----.| | .----..-----.-----. | | | __ | ---'| '--.| .-'| | | | | | | | |--- || --'| | | ' | | | | '---'---'--'--'--. |-----''----''--' '-----'-'-'-' -' | '---' The Angstrom Distribution beaglebone ttyO0 Angstrom v2012.12 - Kernel 3.8.13 beaglebone login: root Last login: Sat Jan 1 02:57:42 UTC 2000 on ttyO0 root@beaglebone:~# lsb_release -a Distributor ID: Angstrom Description: Angstrom GNU/Linux v2012.12 (Core edition) Release: v2012.12 Codename: Core edition |
Fiz os testes com a distribuição Angstrom. Para logar, o usuário é root e não precisa de senha.
Divirta-se!
Sergio Prado
