dcf77onPi.c File Reference

This program is for using DCF77 AM receivers on a Pi. More...

#include "weGPIOd.h"
#include "weUtil.h"
#include <getopt.h>
#include "weLockWatch.h"
#include <errno.h>
#include "weDCF77.h"

Functions
int	main (int argc, char **argv)
	The program. More...

Variables
uint32_t	lesDCFout
	Bit mask of all outputs set by dcfOut.
int	outScn []
	GPIO assignments, default pi4scann.
int	outTrf []
	GPIO assignments, default piTrafficShield.
char const	outTxt [][8]
	Names for outputs: LEDs and control.

Detailed Description

This program is for using DCF77 AM receivers on a Pi.

            '
Copyright (c)    2021 2023    Albrecht Weinert
weinert-automation.de         a-weinert.de
 
  /         /      /\
 /         /___   /  \      |
 \        /____\ /____\ |  _|__
  \  /\  / \    /      \|   |
   \/  \/   \__/        \__/|_
 
 
 
Revision history
Rev. 58 19.06.2024
Rev. 236 01.02.2021 : new  (testOnPi fork)
   .

Purpose

This program handles the modulation signal of an AM (amplitude modulation) DCF77 receiver. DCF77 is the German long wave transmitter to broadcast the official/legal time.
Up to Revision 239++ April 2021 it is merely for testing AM receivers by logging every signal and timing.

By program options any GPIO can be chosen for the AM signal, as well as the signal polarity, filter modes and much more. The reception can be observed by up to 6 output signals respectively LEDs. The DCF77 signal is decoded and can be logged.

Options are:

--useWD --noWD      use the watchdog / do not use it (default)
--useLock --noLock  use the IO singleton lock / do not use it (default)
--GPIO    -G   GPIO number for the AM signal input
--pin     -p   IO connector pin number for the AM signal input
--invert --noInvert invert standard polarity / do not (default)
--pullnone --pullup --pulldown  pull resistor no / up (default) / down
--pullkeep           keep input's pull resistor setting as is
--glitch  -g         set glitch filter time in μs

Use "dcf77onPi --help" to see the actual list.

GPIO usage

The program may use every GPIO by command line parameter.

Timing

Data for every modulation period are put asynchronously in a FIFO.

The program has a cyclic process control (in SPS manner, by weUtil.h weUtil.c etc). We use

a) a 10 ms cycle to sample the FiFo and do all other work, like
   decoding, logging etc.
b) so far no other cycle

Library usage

The program uses some standard libraries plus own libraries in weRasp/..c and include/..h, namely weGPIOd, sysUtil etc..

Prerequisites

As the program may use GPIO via pigpiod and the watchdog it requires them both available, e.g. by a (sudo crontab) cronjob

@reboot  /usr/local/bin/pigpiod  -s 10
@reboot  sleep 5 && chmod a+=rw /dev/watchdog
@reboot  chmod a+=rw /dev/hidraw0

Compile, build, load

cross-compile by:

make TARGET=pi4scann PROGRAM=dcf77onPi clean all 

program by:

make PROGRAM=dcf77onPi TARGET=pi4you FTPuser=pi:piPi progapp 

Function Documentation

main()

int main	(	int	argc,
		char **	argv
	)

The program.

Run by: dcf77onPi [options

For options see: dcf77onPi –help

memcpy(dfc77ringBrecPer[readInd].sysClk, "hh:mm:ss.mil\0", 13); // init as hh:mm:ss