Moxa Technologies EM-1240-LX user manual RTC Real-time Clock, Buzzer, Uart Interface

EM-1240-LX User’s Manual EM-1240-LX Device API

RTC (Real-time Clock)

The device node is located at /dev/rtc. The EM-1240-LX supports µClinux standard simple RTC control. You must include <linux/rtc.h> to use these functions.

1. Function: RTC_RD_TIME

int ioctl(fd, RTC_RD_TIME, struct rtc_time *time); Description: Reads time information from RTC.

2. Function: RTC_SET_TIME

int ioctl(fd, RTC_SET_TIME, struct rtc_time *time); Description: Sets RTC time.

Buzzer

The device node is located at /dev/console. The EM-1240-LX supports µClinux standard buzzer control. The EM-1240-LX’s buzzer runs at a fixed frequency of 100 Hz. You must include <sys/kd.h> to use these functions.

1. Function: KDMKTONE

ioctl(fd, KDMKTONE, unsigned int arg);

Description: Buzzer will beep, as stipulated by the function arguments.

UART Interface

The normal tty device node is located at /dev/ttyM0…ttyM1, and modem tty device node is located at /dev/com0 … com1. The EM-1240-LX Series supports µClinux standard termios control. Moxa UART Device API supports the configuration of ttyM0 to ttyM1 as RS-232/422/485. To use these functions, after the Tool Chain package is installed, include <moxadevice.h> in your application.

#define RS232_MODE	0
#define RS485_2WIRE_MODE	1
#define RS422_MODE	2
#define RS485_4WIRE_MODE	3

1. Function: MOXA_SET_OP_MODE

int mode;

mode=which mode you want to set;

int ioctl(fd, MOXA_SET_OP_MODE, &mode)

Description: Sets the interface mode.

2. Function: MOXA_GET_OP_MODE

int mode;

int ioctl(fd, MOXA_GET_OP_MODE, &mode)

Description: Gets the interface mode.

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