Hi all,
I am writing data to a file on my SD card successfully. Unfortunately, When I turn off the Logomatic V2 and re-start it, the new data over-writes the old data. I would like to be able to append the data to the existing file.
I am sure it must be my programming skills (which are beginner level)
Maybe I need to use file16_file_write differently, or another command.
Any ideas? Thank You
Without seeing your code I can’t say exactly, but it should be something pretty easy to fix.
When you turn it on, there will be some sort of initialization of the file? Have a look at that, maybe even try removing it.
Your code is already doing an append when its running, each time it logs data, so see how it’s doing that and maybe convert your initialization code to that append code.
Your not using the stock logomatic firmware are you?
Hi Gussy,
Thanks for your reply!
I tried to insert some code to show you, but I got ‘you have entered a forbidden word’ warning?!
I’ll try again soon. Anyway, the initialization routine you mentioned - could it be here after Boot up()?
{
CCR &= ~(1<<0); //Disable the RTC
CCR |= (1<<1); //Reset the RTC
YEAR=2009;
MONTH=6;
DOM=9;
DOW=0;
DOY=0;
HOUR=13;
MIN=43;
SEC=0;
CCR &= ~(1<<1); //Enable the RTC
CCR |= (1<<0); //Enable the Clock
boot_up(); //Init LPC, IO pins, and FAT
//log_string(“Log started\r\n”);
set_pin_mode(1, “DI”);
char str_data[128];
string_printf(str_data, “%02d/%02d/%04d,%02d:%02d:%02d Data Goes Here\r\n”, DOM, MONTH, YEAR, HOUR, MIN, SEC);
log_string(str_data);
write_digital_pin(STAT1, ON); //Turn on LED
delay_ms(50);
write_digital_pin(STAT1, OFF); //Turn off LED
delay_ms(250);
delay_ms(700);
fat16_close_file(handle);
}
void log_string(char *buf)
{
int stringSize = strlen(buf);
fat16_write_file(handle, (unsigned char*)buf, stringSize);
sd_raw_sync();
}
//Basic file init and stuff
void boot_up(void)
{
set_pin_mode(STAT0, “DO”); //Set status LEDs as outputs
set_pin_mode(STAT1, “DO”);
rprintf_devopen(putc_serial0); //Open up serial port 0 for debugging
card_init(); //Init SD card interface
//Creat the main log file
char name[32];
string_printf(name,“PKDATA.txt”);
handle = root_open(name);
sd_raw_sync();
//Setup TIMER1 to run
T1TCR = 0; //Reset Timer1
T1PR = 60000; //Set prescalar to 60,000 - every tick is 1ms
T1TCR = 1; //Start Timer1
flash_it(50); //Flash Status Lights
}
This the the code you need to focus on here:
//Creat the main log file
char name[32];
string_printf(name,"PKDATA.txt");
handle = root_open(name);
sd_raw_sync();
Specifically the root_open() function, you should find it in the rootdir.c file.
The function root_open should look like this:
struct fat16_file_struct * root_open(char* name)
{
return(open_file_in_dir(fs,dd,name));
}
I’ve been meaning to release this for a while and it should be just what you’re looking for. It’s available [here.
If you do use it, please get back to me with whether or not it worked correctly. Thanks!](LogomaticV2: Firmware to append to a single file - SparkFun Electronics Forum)
Thank you gussy and Iquaba. You were both correct.
gussy - the ‘open_root’ function now looks like this:
string_printf(name, "MainLog.txt");
if(!root_file_exists(name)){
handle = root_open_new(name);
}
else{
handle = root_open_append(name);
}
Iquaba - You will recognize the code from your timely work!
Thank you both again!
This works but overwrites the information in the file does it not?
For the sake of people who search and find this, the firmware is available here:
Let me know if people are still finding this useful!