I'm trying to bring up CAN bus client application based on CanFestival.
When I try to read from the CAN server readNetworkDict() fails in the following code
offset = d->firstIndex->SDO_CLT;
lastIndex = d->lastIndex->SDO_CLT;
if (offset == 0) {
MSG_ERR(0x1AC6, "No SDO client index found for nodeId ", nodeId);
return 0xFF;
}
and this is SDO_CLT in my dictionary.
const quick_index GoldTwitter_firstIndex = {
3, /* SDO_SVR */
0, /* SDO_CLT */
4, /* PDO_RCV */
5, /* PDO_RCV_MAP */
6, /* PDO_TRS */
7 /* PDO_TRS_MAP */
};
Having only a couple of days of CAN bus experience I have some basic questions.
What is SDO_CLT?
Is it being zero indicates the problem in dictionary generation or I have to initialize it during runtime?
You must define the SDO parameters in the dictionary, something like this:
Related
I am new to writing functions in C to be used with SQL. So far, I have looked at this example which executes a query using SPI. However, it prints the result as a log message. I was wondering how would this example have to change for me to return the result as a normal query (normal as in how I can view it when I execute a SQL query in pgAdmin)?
User-defined functions written in C may be what you want. https://www.postgresql.org/docs/current/xfunc-c.html#id-1.8.3.13.11
A complete example of returning a composite type looks like:
PG_FUNCTION_INFO_V1(retcomposite);
Datum
retcomposite(PG_FUNCTION_ARGS)
{
FuncCallContext *funcctx;
int call_cntr;
int max_calls;
TupleDesc tupdesc;
AttInMetadata *attinmeta;
/* stuff done only on the first call of the function */
if (SRF_IS_FIRSTCALL())
{
MemoryContext oldcontext;
/* create a function context for cross-call persistence */
funcctx = SRF_FIRSTCALL_INIT();
/* switch to memory context appropriate for multiple function calls */
oldcontext = MemoryContextSwitchTo(funcctx->multi_call_memory_ctx);
/* total number of tuples to be returned */
funcctx->max_calls = PG_GETARG_UINT32(0);
/* Build a tuple descriptor for our result type */
if (get_call_result_type(fcinfo, NULL, &tupdesc) != TYPEFUNC_COMPOSITE)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("function returning record called in context "
"that cannot accept type record")));
/*
* generate attribute metadata needed later to produce tuples from raw
* C strings
*/
attinmeta = TupleDescGetAttInMetadata(tupdesc);
funcctx->attinmeta = attinmeta;
MemoryContextSwitchTo(oldcontext);
}
/* stuff done on every call of the function */
funcctx = SRF_PERCALL_SETUP();
call_cntr = funcctx->call_cntr;
max_calls = funcctx->max_calls;
attinmeta = funcctx->attinmeta;
if (call_cntr < max_calls) /* do when there is more left to send */
{
char **values;
HeapTuple tuple;
Datum result;
/*
* Prepare a values array for building the returned tuple.
* This should be an array of C strings which will
* be processed later by the type input functions.
*/
values = (char **) palloc(3 * sizeof(char *));
values[0] = (char *) palloc(16 * sizeof(char));
values[1] = (char *) palloc(16 * sizeof(char));
values[2] = (char *) palloc(16 * sizeof(char));
snprintf(values[0], 16, "%d", 1 * PG_GETARG_INT32(1));
snprintf(values[1], 16, "%d", 2 * PG_GETARG_INT32(1));
snprintf(values[2], 16, "%d", 3 * PG_GETARG_INT32(1));
/* build a tuple */
tuple = BuildTupleFromCStrings(attinmeta, values);
/* make the tuple into a datum */
result = HeapTupleGetDatum(tuple);
/* clean up (this is not really necessary) */
pfree(values[0]);
pfree(values[1]);
pfree(values[2]);
pfree(values);
SRF_RETURN_NEXT(funcctx, result);
}
else /* do when there is no more left */
{
SRF_RETURN_DONE(funcctx);
}
}
You can combine this with SPI.
I'm trying to program LPC824 microcontroller board ([https://www.switch-science.com/catalog/2265/][1]) with LPCOpen.
I'm using it with LPCLink 2 debugger board.
My goal is to get some information from the "pressure sensor" with an ADC.
My code stops with a HardFault when executing a NVIC_EnableIRQ function(on line: 92).
If I don't use "NVIC interrupt controller" then my code works and I can get value from sensor with ADC.
What I am doing wrong?
Here is my adc.c code:
#include "board.h"
static volatile int ticks;
static bool sequenceComplete = false;
static bool thresholdCrossed = false;
#define TICKRATE_HZ (100) /* 100 ticks per second */
#define BOARD_ADC_CH 2
/**
* #brief Handle interrupt from ADC sequencer A
* #return Nothing
*/
void ADC_SEQA_IRQHandler(void) {
uint32_t pending;
/* Get pending interrupts */
pending = Chip_ADC_GetFlags(LPC_ADC);
/* Sequence A completion interrupt */
if (pending & ADC_FLAGS_SEQA_INT_MASK) {
sequenceComplete = true;
}
/* Threshold crossing interrupt on ADC input channel */
if (pending & ADC_FLAGS_THCMP_MASK(BOARD_ADC_CH)) {
thresholdCrossed = true;
}
/* Clear any pending interrupts */
Chip_ADC_ClearFlags(LPC_ADC, pending);
}
/**
* #brief Handle interrupt from SysTick timer
* #return Nothing
*/
void SysTick_Handler(void) {
static uint32_t count;
/* Every 1/2 second */
if (count++ == TICKRATE_HZ / 2) {
count = 0;
Chip_ADC_StartSequencer(LPC_ADC, ADC_SEQA_IDX);
}
}
/**
* #brief main routine for ADC example
* #return Function should not exit
*/
int main(void) {
uint32_t rawSample;
int j;
SystemCoreClockUpdate();
Board_Init();
/* Setup ADC for 12-bit mode and normal power */
Chip_ADC_Init(LPC_ADC, 0);
Chip_ADC_Init(LPC_ADC, ADC_CR_MODE10BIT);
/* Need to do a calibration after initialization and trim */
Chip_ADC_StartCalibration(LPC_ADC);
while (!(Chip_ADC_IsCalibrationDone(LPC_ADC))) {
}
/* Setup for maximum ADC clock rate using sycnchronous clocking */
Chip_ADC_SetClockRate(LPC_ADC, ADC_MAX_SAMPLE_RATE);
Chip_ADC_SetupSequencer(LPC_ADC, ADC_SEQA_IDX,
(ADC_SEQ_CTRL_CHANSEL(BOARD_ADC_CH) | ADC_SEQ_CTRL_MODE_EOS));
Chip_Clock_EnablePeriphClock(SYSCTL_CLOCK_SWM);
Chip_SWM_EnableFixedPin(SWM_FIXED_ADC2);
Chip_Clock_DisablePeriphClock(SYSCTL_CLOCK_SWM);
/* Setup threshold 0 low and high values to about 25% and 75% of max */
Chip_ADC_SetThrLowValue(LPC_ADC, 0, ((1 * 0xFFF) / 4));
Chip_ADC_SetThrHighValue(LPC_ADC, 0, ((3 * 0xFFF) / 4));
Chip_ADC_ClearFlags(LPC_ADC, Chip_ADC_GetFlags(LPC_ADC));
Chip_ADC_EnableInt(LPC_ADC,
(ADC_INTEN_SEQA_ENABLE | ADC_INTEN_OVRRUN_ENABLE));
Chip_ADC_SelectTH0Channels(LPC_ADC, ADC_THRSEL_CHAN_SEL_THR1(BOARD_ADC_CH));
Chip_ADC_SetThresholdInt(LPC_ADC, BOARD_ADC_CH, ADC_INTEN_THCMP_CROSSING);
/* Enable ADC NVIC interrupt */
NVIC_EnableIRQ(ADC_SEQA_IRQn);
Chip_ADC_EnableSequencer(LPC_ADC, ADC_SEQA_IDX);
SysTick_Config(SystemCoreClock / TICKRATE_HZ);
/* Endless loop */
while (1) {
/* Sleep until something happens */
__WFI();
if (thresholdCrossed) {
thresholdCrossed = false;
printf("********ADC threshold event********\r\n");
}
/* Is a conversion sequence complete? */
if (sequenceComplete) {
sequenceComplete = false;
/* Get raw sample data for channels 0-11 */
for (j = 0; j < 12; j++) {
rawSample = Chip_ADC_GetDataReg(LPC_ADC, j);
/* Show some ADC data */
if (rawSample & (ADC_DR_OVERRUN | ADC_SEQ_GDAT_DATAVALID)) {
printf("Chan: %d Val: %d\r\n", j, ADC_DR_RESULT(rawSample));
printf("Threshold range: 0x%x ",
ADC_DR_THCMPRANGE(rawSample));
printf("Threshold cross: 0x%x\r\n",
ADC_DR_THCMPCROSS(rawSample));
printf("Overrun: %s ",
(rawSample & ADC_DR_OVERRUN) ? "true" : "false");
printf("Data Valid: %s\r\n\r\n",
(rawSample & ADC_SEQ_GDAT_DATAVALID) ?
"true" : "false");
}
}
}
}
}
Hard fault usually means that you try to execute code outside allowed addresses. If you have not registered the interrupt in the vector table but enabled it, the MCU will jump to whatever address that's written there instead, after which the program crashes.
How to fix that depends on tool chain. Assuming LPCXpresso, you have several options to set up libraries (I don't know about LPCOpen specifically), so where to find the vector table is different from case to case. However, this works quite similar on most MCUs, ARM or not. Somewhere in a "crt start-up" file you should have something along the lines of this:
void (* const g_pfnVectors[])(void) = ...
This is an array of function pointers which will be the vector table allocated in memory at address 0 on Cortex M. You have to place your function at the relevant interrupt vector. For example it may say something like
PIN_INT0_IRQHandler, // PIO INT0
If that's the interrupt you should implement, then you replace that line:
#include "my_irq_stuff.h"
...
void (* const g_pfnVectors[])(void) =
...
my_INT0, // PIO INT0
Assuming my_irq_stuff.h contains the function prototype my_INT0 for the interrupt service routine. The actual routine should be implemented in the corresponding .c file.
I am trying to understand fcntl system call , which has this structure as the second parameter:
struct flock fl;
int fd;
fl.l_type = F_WRLCK; /* F_RDLCK, F_WRLCK, F_UNLCK */
fl.l_whence = SEEK_SET; /* SEEK_SET, SEEK_CUR, SEEK_END */
fl.l_start = 0; /* Offset from l_whence */
fl.l_len = 0; /* length, 0 = to EOF */
fl.l_pid = getpid(); /* our PID
I want to know what exactly is fl.l_start
so for example if I make it fl.l_start = 5, does that mean that protection is guaranteed only beyond 5 bytes from the beginning?
(i.e before 5 bytes, no lock is there so, all the processes can have access to it in a non-cooperative manner.)
I'd like to know how to send a frame once I've created it.
I've got the next:
int
arp_send(libnet_t *l, int op, u_char *sha, in_addr_t spa, u_char *tha, in_addr_t tpa)
{
libnet_ptag_t t;
if (sha == NULL &&
(sha = (u_char *)libnet_get_hwaddr(l)) == NULL) {
return (-1);
}
if (spa == 0) {
if ((spa = libnet_get_ipaddr4(l)) == -1)
return (-1);
}
if (tha == NULL)
tha = (u_char *)"\xff\xff\xff\xff\xff\xff";
libnet_clear_packet(l);
/*
* Build the packet, remmebering that order IS important. We must
* build the packet from lowest protocol type on up as it would
* appear on the wire. So for our ARP packet:
*
* -------------------------------------------
* | Ethernet | ARP |
* -------------------------------------------
* ^ ^
* |------------------ |
* libnet_build_ethernet()--| |
* |
* libnet_build_arp()-----------|
*/
t = libnet_build_arp(
ARPHRD_ETHER, /* hardware addr */
ETHERTYPE_IP, /* protocol addr */
6, /* hardware addr size */
4, /* protocol addr size */
op, /* operation type */
sha, /* sender hardware addr */
(u_int8_t *)&spa, /* sender protocol addr */
tha, /* target hardware addr */
(u_int8_t *)&tpa, /* target protocol addr */
NULL, /* payload */
0, /* payload size */
l, /* libnet context */
0); /* libnet id */
if (t == -1)
{
fprintf(stderr, "Can't build ARP header: %s\n", libnet_geterror(l));
return -1;
}
t = libnet_autobuild_ethernet(
tha, /* ethernet destination */
ETHERTYPE_ARP, /* protocol type */
l); /* libnet handle */
if (t == -1)
{
fprintf(stderr, "Can't build ethernet header: %s\n",
libnet_geterror(l));
return -1;
}
return libnet_write(l);
}
I found that code on the net, which creates from nothing an arp packet. I do understand everything but the return, because I don't find the "send" command.
thank you.
libnet_write() does that.
Writes a prebuilt packet to the network. The function assumes that l was
previously initialized (via a call to libnet_init()) and that a
previously constructed packet has been built inside this context (via one or
more calls to the libnet_build* family of functions) and is ready to go.
Depending on how libnet was initialized, the function will write the packet
to the wire either via the raw or link layer interface. The function will
also bump up the internal libnet stat counters which are retrievable via
libnet_stats().
#param l pointer to a libnet context
#return the number of bytes written, -1 on error
as per as comment in libnet/libnet-functions.h
I am on OSX Mountain Lion and am trying to retrieve a processes' name using its PID.
The following is the code I am using:
pid_t pid = 10687;
char pathBuffer [PROC_PIDPATHINFO_MAXSIZE] = "";
char nameBuffer [256] = "";
int sizeOfVal = sizeof(nameBuffer);
proc_pidpath(pid, pathBuffer, sizeof(pathBuffer));
proc_name(pid, nameBuffer, sizeof(nameBuffer));
NSLog(#"Path: %s\n Name: %s\n", pathBuffer, nameBuffer);
The code above is able to retrieve the name properly, however it only retrieves the first 15 characters and "ignores" the rest. Note this is not a problem with displaying the name, but with retrieving it. The problem is not with the rest of my application as I am testing the above code in a standalone application. Also note that I tried changing the PID, but regardless of what PID I try the code only retrieves the first 15 characters of the name. Path retrieval works perfectly.
Does anyone have any ideas about what I am doing wrong?
The function looks at the value is the struct proc_bsdshortinfo. It is limited to return a 16 byte string, or 15 readable characters when including the null terminator.
From sys/param.h:
#define MAXCOMLEN 16 /* max command name remembered */
From sys/proc_info.h:
struct proc_bsdshortinfo {
uint32_t pbsi_pid; /* process id */
uint32_t pbsi_ppid; /* process parent id */
uint32_t pbsi_pgid; /* process perp id */
uint32_t pbsi_status; /* p_stat value, SZOMB, SRUN, etc */
char pbsi_comm[MAXCOMLEN]; /* upto 16 characters of process name */
uint32_t pbsi_flags; /* 64bit; emulated etc */
uid_t pbsi_uid; /* current uid on process */
gid_t pbsi_gid; /* current gid on process */
uid_t pbsi_ruid; /* current ruid on process */
gid_t pbsi_rgid; /* current tgid on process */
uid_t pbsi_svuid; /* current svuid on process */
gid_t pbsi_svgid; /* current svgid on process */
uint32_t pbsi_rfu; /* reserved for future use*/
};
EDIT: To get around this, get the last path component:
pid_t pid = 3051;
char pathBuffer [PROC_PIDPATHINFO_MAXSIZE];
proc_pidpath(pid, pathBuffer, sizeof(pathBuffer));
char nameBuffer[256];
int position = strlen(pathBuffer);
while(position >= 0 && pathBuffer[position] != '/')
{
position--;
}
strcpy(nameBuffer, pathBuffer + position + 1);
printf("path: %s\n\nname:%s\n\n", pathBuffer, nameBuffer);