Rtc (real-time clock), Buzzer, Uart interface – Moxa Technologies EM-1240-LX User Manual
Page 49

EM-1240-LX User’s Manual
EM-1240-LX Device API
5-2
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
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
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
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.