I would like to ask for an advice about my code and show me implementing model of yours. I am implementing program in the code below, and make this code the basis.
Now, I implemented receiver function for xmodem, but it's not working.
"xmodem_receive" called in main function just once printed "Sending C ping ...." as printf and , finished.
Sending xmodem is working as being shown below.
Receving Xmodem is not working.It finished before receiving data.
So I would like to ask
1)Why my xmodem receive function is not working?
2)Why STX is present as "K" ,and that could go through IF statement
if(recSTX == X_STX){
printf("STX is %c\n", &recSTX);
}else{
printf("Garabage payload %c\n", &recSTX);
}
This is my implementation function
static int xmodem_receive(int serial_fd, char* filename, int _crc){
int skip = 0;
uint8_t sdCRC = 'C';
uint8_t sdACK = X_ACK;
uint8_t eof = X_EOF;
uint8_t sdNAK = X_NAK;
uint8_t recSTX; // receive SOH from chunk
uint8_t recBlk; // receive blk from chunk
uint8_t recNegBlk; // receive blk negative from chunk
uint8_t recData[1024]; // receive data from chunk
uint16_t recChksum;
FILE *fp;
int ret, fd;
struct stat stat;
// If we want to receive, We have to send NAK to Sendor.
/* Writing as binary */
fp = fopen(filename, "wb");
//Send NAK still read SOH that header of one data chunks
while(1){
char status;
printf("Waiting for sender ping ...");
fflush(stdout);
//
do {
if(_crc){
printf("Send C ping....\n");
ret = write(serial_fd, &sdCRC, sizeof(sdCRC));
}else{
// send NAK before read SOH
printf("Send NAK ping....\n");
ret = write(serial_fd, &sdNAK, sizeof(sdNAK));
} // after sending NAK,receiving　SOH from chunk
fflush(stdout);
ret = read(serial_fd, &recSTX, sizeof(recSTX));
if(recSTX == X_STX){
printf("STX is %c\n", &recSTX);
}else{
printf("Garabage payload %c\n", &recSTX);
}
fflush(stdout);
if (ret != sizeof(recSTX)) {
printf("Not working");
fflush(stdout);
perror("read");
return -errno;
}
} while (recSTX != X_STX);
//So next, receiving blk
ret = read(serial_fd, &recBlk, sizeof(recBlk));
printf("Block Num is %d\n", recBlk);
fflush(stdout);
if (ret != sizeof(recBlk)) {
perror("read");
return -errno;
}
ret = read(serial_fd, &recNegBlk, sizeof(recNegBlk));
printf("Negative Block Num is %d\n", recNegBlk);
fflush(stdout);
if (ret != sizeof(recNegBlk)) {
perror("read");
return -errno;
}
ret = read(serial_fd, (void *)&recData, sizeof(recData));
printf("Data buffer is %c\n", &recData);
fflush(stdout);
if (ret != sizeof(recData)) {
perror("read");
return -errno;
}
ret = read(serial_fd, &recChksum, sizeof(recChksum));
printf("Check sum is %c", &recChksum);
fflush(stdout);
if (ret != sizeof(recChksum)) {
perror("read");
return -errno;
}
// data block number check
if(recBlk == 0xff - recNegBlk){
perror("read");
return -errno;
}
// data integrity check
if(recChksum == swap16(crc16(recData, sizeof(recData)))){
perror("read");
return -errno;
}
// check of appended "0xff" from end of data to end of chunk in chunk
unsigned char *ptr = recData;
ptr += sizeof(recData);
while(*ptr == 0xff){
ptr--;
}
fwrite(recData, (ptr - recData),1,fp); // write Datas bytes from our buffer
// set skip flag or end connect
ret = write(serial_fd, &eof, sizeof(uint8_t));
if (ret != sizeof(eof) || ret != sizeof(X_STX)){
return -errno;
}else{
if(ret == X_STX){
skip = 1;
}else if(ret == EOF){
printf("EOF ...");
ret = write(serial_fd, &sdACK, sizeof(sdACK));
break;
}else{
return -errno;
}
}
}
printf("done.\n");
fclose(fp);
return 0;
}
And This is full code.
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <string.h>
#include <errno.h>
#include <unistd.h>
#include <fcntl.h>
#include <termios.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/mman.h>
#include <string>
#define X_STX 0x02
#define X_ACK 0x06
#define X_NAK 0x15
#define X_EOF 0x04
#define min(a, b) ((a) < (b) ? (a) : (b))
struct xmodem_chunk {
uint8_t start;
uint8_t block;
uint8_t block_neg;
uint8_t payload[1024];
uint16_t crc;
} __attribute__((packed));
#define CRC_POLY 0x1021
static uint16_t crc_update(uint16_t crc_in, int incr)
{
uint16_t xor1 = crc_in >> 15;
uint16_t out1 = crc_in << 1;
if(incr)
out1++;
if(xor1)
out1 ^= CRC_POLY; // xor 0b1000000100001
return out1;
}
static uint16_t crc16(const uint8_t *data, uint16_t size)
{
uint16_t crc, i;
for (crc = 0; size > 0; size--, data++)
for (i = 0x80; i; i >>= 1)
crc = crc_update(crc, *data & i);
for (i = 0; i < 16; i++)
crc = crc_update(crc, 0);
return crc;
}
static uint16_t swap16(uint16_t in)
{
return (in >> 8) | ((in & 0xff) << 8);
}
enum {
PROTOCOL_XMODEM,
PROTOCOL_YMODEM,
};
static int xmodem_receive(int serial_fd, char* filename, int _crc){
int skip = 0;
uint8_t sdCRC = 'C';
uint8_t sdACK = X_ACK;
uint8_t eof = X_EOF;
uint8_t sdNAK = X_NAK;
uint8_t recSTX; // receive SOH from chunk
uint8_t recBlk; // receive blk from chunk
uint8_t recNegBlk; // receive blk negative from chunk
uint8_t recData[1024]; // receive data from chunk
uint16_t recChksum;
FILE *fp;
int ret, fd;
struct stat stat;
// If we want to receive, We have to send NAK to Sendor.
/* Writing as binary */
fp = fopen(filename, "wb");
//Send NAK still read SOH that header of one data chunks
while(1){
char status;
printf("Waiting for sender ping ...");
fflush(stdout);
//
do {
if(_crc){
printf("Send C ping....\n");
ret = write(serial_fd, &sdCRC, sizeof(sdCRC));
}else{
// send NAK before read SOH
printf("Send NAK ping....\n");
ret = write(serial_fd, &sdNAK, sizeof(sdNAK));
} // after sending NAK,receiving　SOH from chunk
fflush(stdout);
ret = read(serial_fd, &recSTX, sizeof(recSTX));
if(recSTX == X_STX){
printf("STX is %c\n", &recSTX);
}else{
printf("Garabage payload %c\n", &recSTX);
}
fflush(stdout);
if (ret != sizeof(recSTX)) {
printf("Not working");
fflush(stdout);
perror("read");
return -errno;
}
} while (recSTX != X_STX);
//So next, receiving blk
ret = read(serial_fd, &recBlk, sizeof(recBlk));
printf("Block Num is %d\n", recBlk);
fflush(stdout);
if (ret != sizeof(recBlk)) {
perror("read");
return -errno;
}
ret = read(serial_fd, &recNegBlk, sizeof(recNegBlk));
printf("Negative Block Num is %d\n", recNegBlk);
fflush(stdout);
if (ret != sizeof(recNegBlk)) {
perror("read");
return -errno;
}
ret = read(serial_fd, (void *)&recData, sizeof(recData));
printf("Data buffer is %c\n", &recData);
fflush(stdout);
if (ret != sizeof(recData)) {
perror("read");
return -errno;
}
ret = read(serial_fd, &recChksum, sizeof(recChksum));
printf("Check sum is %c", &recChksum);
fflush(stdout);
if (ret != sizeof(recChksum)) {
perror("read");
return -errno;
}
// data block number check
if(recBlk == 0xff - recNegBlk){
perror("read");
return -errno;
}
// data integrity check
if(recChksum == swap16(crc16(recData, sizeof(recData)))){
perror("read");
return -errno;
}
// check of appended "0xff" from end of data to end of chunk in chunk
unsigned char *ptr = recData;
ptr += sizeof(recData);
while(*ptr == 0xff){
ptr--;
}
fwrite(recData, (ptr - recData),1,fp); // write Datas bytes from our buffer
// set skip flag or end connect
ret = write(serial_fd, &eof, sizeof(uint8_t));
if (ret != sizeof(eof) || ret != sizeof(X_STX)){
return -errno;
}else{
if(ret == X_STX){
skip = 1;
}else if(ret == EOF){
printf("EOF ...");
ret = write(serial_fd, &sdACK, sizeof(sdACK));
break;
}else{
return -errno;
}
}
}
printf("done.\n");
fclose(fp);
return 0;
}
static int xymodem_send(int serial_fd, const char *filename, int protocol, int wait)
{
size_t len;
int ret, fd;
uint8_t answer;
struct stat stat;
const uint8_t *buf;
uint8_t eof = X_EOF;
struct xmodem_chunk chunk;
int skip_payload = 0;
fd = open(filename, O_RDONLY);
if (fd < 0) {
perror("open");
return -errno;
}
fstat(fd, &stat);
len = stat.st_size;
buf = static_cast<uint8_t*>(mmap(NULL, len, PROT_READ, MAP_PRIVATE, fd, 0));
if (!buf) {
perror("mmap");
return -errno;
}
if (wait) {
printf("Waiting for receiver ping ...");
fflush(stdout);
do {
ret = read(serial_fd, &answer, sizeof(answer));
if (ret != sizeof(answer)) {
perror("read");
return -errno;
}
} while (answer != 'C');
printf("done.\n");
}
printf("Sending %s ", filename);
if (protocol == PROTOCOL_YMODEM) {
strncpy((char *) chunk.payload, filename, sizeof(chunk.payload));
chunk.block = 0;
skip_payload = 1;
} else {
chunk.block = 1;
}
chunk.start = X_STX;
while (len) {
size_t z = 0;
int next = 0;
char status;
if (!skip_payload) {
z = min(len, sizeof(chunk.payload));
memcpy(chunk.payload, buf, z);
memset(chunk.payload + z, 0xff, sizeof(chunk.payload) - z);
} else {
skip_payload = 0;
}
chunk.crc = swap16(crc16(chunk.payload, sizeof(chunk.payload)));
chunk.block_neg = 0xff - chunk.block;
ret = write(serial_fd, &chunk, sizeof(chunk));
if (ret != sizeof(chunk))
return -errno;
ret = read(serial_fd, &answer, sizeof(answer));
if (ret != sizeof(answer))
return -errno;
switch (answer) {
case X_NAK:
status = 'N';
break;
case X_ACK:
status = '.';
next = 1;
break;
default:
status = '?';
break;
}
printf("%c", status);
fflush(stdout);
if (next) {
chunk.block++;
len -= z;
buf += z;
}
}
ret = write(serial_fd, &eof, sizeof(eof));
if (ret != sizeof(eof))
return -errno;
/* send EOT again for YMODEM */
if (protocol == PROTOCOL_YMODEM) {
ret = write(serial_fd, &eof, sizeof(eof));
if (ret != sizeof(eof))
return -errno;
}
printf("done.\n");
return 0;
}
static int open_serial(const char *path, int baud)
{
int fd;
struct termios tty;
fd = open(path, O_RDWR | O_SYNC);
if (fd < 0) {
perror("open");
return -errno;
}
memset(&tty, 0, sizeof(tty));
if (tcgetattr(fd, &tty) != 0) {
perror("tcgetattr");
return -errno;
}
cfsetospeed(&tty, baud);
cfsetispeed(&tty, baud);
tty.c_cflag = (tty.c_cflag & ~CSIZE) | CS8; // 8-bit chars
tty.c_iflag &= ~IGNBRK; // disable break processing
tty.c_lflag = 0; // no signaling chars, no echo,
// no canonical processing
tty.c_oflag = 0; // no remapping, no delays
tty.c_cc[VMIN] = 1; // read doesn't block
tty.c_cc[VTIME] = 5; // 0.5 seconds read timeout
tty.c_iflag &= ~(IXON | IXOFF | IXANY); // shut off xon/xoff ctrl
tty.c_cflag |= (CLOCAL | CREAD); // ignore modem controls,
// enable reading
tty.c_cflag &= ~(PARENB | PARODD); // shut off parity
tty.c_cflag &= ~CSTOPB;
tty.c_cflag &= ~CRTSCTS;
if (tcsetattr(fd, TCSANOW, &tty) != 0) {
perror("tcsetattr");
return -errno;
}
return fd;
}
static void dump_serial(int serial_fd)
{
char in;
for (;;) {
read(serial_fd, &in, sizeof(in));
printf("%c", in);
fflush(stdout);
}
}
#ifdef TEST_XMODEM_RECEIVE
#endif // TEST_XMODEM_RECEIVE
int main(int argc, char **argv)
{
int a, ret, serial_fd;
printf("STX: %c\n", X_STX);
printf("ACK: %c\n", X_ACK);
printf("NAK: %c\n", X_NAK);
printf("EOF: %c\n", X_EOF);
fflush(stdout);
serial_fd = open_serial("/dev/ttyUSB0", 115200);
if (serial_fd < 0)
return -errno;
if(std::string(argv[2]) == "0" || std::string(argv[2]) == "0"){
ret = xymodem_send(serial_fd, argv[1], PROTOCOL_XMODEM, 1);
if (ret < 0)
return ret;
}
if(std::string(argv[2]) == "1"){
ret = xmodem_receive(serial_fd, argv[1], 1);
if (ret < 0)
return ret;
}
return 0;
}
Thanks for looking through my questions.