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Overview
The Serial Console and Serial Terminal are tools, used to communicate with devices and other systems that are interconnected via the serial port. The serial terminal may be used to monitor and configure many devices - including modems, network devices (including MikroTik routers), and any device that can be connected to a serial (asynchronous) port.
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It allows data-only traffic on the cross-connected Rx/Tx lines. Hardware flow control is not possible with this type of cable. The only way to perform flow control is with software flow control using the XOFF and XON characters.
Null Modem With
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Loopback Handshake
The problem with the first cable is when connected to a device on which hardware flow control is enabled software may hang when checking modem signal lines.
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For RBM33G additional serial header can be attached on GPIO pins U3_RXD, GND, U3_TXD, and 3V3
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CCR Serial Header
The Cloud Core Router series devices have a serial header on the PCB board, called J402 or 100
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What do you want to configure? d - boot delay k - boot key s - serial console n - silent boot o - boot device u - cpu mode f - cpu frequency r - reset booter configuration e - format nand g - upgrade firmware i - board info p - boot protocol b - booter options t - call debug code l - erase license x - exit setup your choice: k - boot key Select key which will enter setup on boot: * 1 - any key 2 - <Delete> key only your chaoicechoice: 2