Moxa V2401-CE [67/108] Baudrate inaccuracy

V2401/2402 Series Linux User’s Manual Programmer Guide

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Baudrate inaccuracy

Divisor = 921600/Target Baud Rate. (Only Integer part)

ENUM = 8 * (921600/Target - Divisor) (Round up or down)

Inaccuracy =( (Target Baud Rate – 921600/(Divisor + (ENUM/8))) / Target Baud Rate )* 100%

E.g.,

To calculate 500000 bps

Divisor = 1, ENUM = 7,

Inaccuracy = 1.7%

* To work reliably, you should set inaccuracy under 2%.

Special Note

1. If the target baudrate is not a special baudrate (e.g. 50, 75, 110, 134, 150, 200, 300, 600, 1200,

1800, 2400, 4800, 9600, 19200, 38400, 57600, 115200, 230400, 460800, 921600), the termios

cflag will be set to the same flag.

2. If you use stty to get the serial information, you will get speed equal to 0 for the special

baudrate.

Digital I/O

Digital Output channels can be set to high or low. The channels are controlled by the function call

set_dout_state( ). Use the digital input channels to detect the state change of the digital input

signal. The DI channels can also be used to detect whether or not the state of a digital signal

changes during a fixed period of time. This can be done by the function call, set_din_event( ).

Return error code definitions:

#define DIO_ERROR_PORT -1 // no such port

#define DIO_ERROR_MODE -2 // no such mode or state

#define DIO_ERROR_CONTROL -3 // open or ioctl fail

#define DIO_ERROR_DURATION -4 // The value of duration is not 0

or not in the range, 40 <= duration <= 3600000 milliseconds (1

hour)

#define DIO_ERROR_DURATION_20MS -5 /

The value of duration must

be a multiple of 20 ms

#define DIO_OK 0

DIN and DOUT definitions:

#define DIO_HIGH 1

#define DIO_LOW 0