Newer
Older
1001
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1009
1010
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1016
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1018
1019
1020
1021
1022
1023
1024
1025
1026
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1028
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1031
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1033
1034
1035
1036
1037
1038
1039
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1044
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1080
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1100
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1102
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1104
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1111
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1132
while (serial_getc () != START_CHAR);
/* get length of packet */
sum = 0;
new_char = serial_getc ();
if ((new_char & 0xE0) == 0)
goto packet_error;
sum += new_char & 0xff;
length = untochar (new_char);
/* get sequence number */
new_char = serial_getc ();
if ((new_char & 0xE0) == 0)
goto packet_error;
sum += new_char & 0xff;
n = untochar (new_char);
--length;
/* NEW CODE - check sequence numbers for retried packets */
/* Note - this new code assumes that the sequence number is correctly
* received. Handling an invalid sequence number adds another layer
* of complexity that may not be needed - yet! At this time, I'm hoping
* that I don't need to buffer the incoming data packets and can write
* the data into memory in real time.
*/
if (n == last_n) {
/* same sequence number, restore the previous state */
k_state = k_state_saved;
k_data_restore ();
} else {
/* new sequence number, checkpoint the download */
last_n = n;
k_state_saved = k_state;
k_data_save ();
}
/* END NEW CODE */
/* get packet type */
new_char = serial_getc ();
if ((new_char & 0xE0) == 0)
goto packet_error;
sum += new_char & 0xff;
k_state = new_char;
--length;
/* check for extended length */
if (length == -2) {
/* (length byte was 0, decremented twice) */
/* get the two length bytes */
new_char = serial_getc ();
if ((new_char & 0xE0) == 0)
goto packet_error;
sum += new_char & 0xff;
len_hi = untochar (new_char);
new_char = serial_getc ();
if ((new_char & 0xE0) == 0)
goto packet_error;
sum += new_char & 0xff;
len_lo = untochar (new_char);
length = len_hi * 95 + len_lo;
/* check header checksum */
new_char = serial_getc ();
if ((new_char & 0xE0) == 0)
goto packet_error;
if (new_char != tochar ((sum + ((sum >> 6) & 0x03)) & 0x3f))
goto packet_error;
sum += new_char & 0xff;
/* --length; */ /* new length includes only data and block check to come */
}
/* bring in rest of packet */
while (length > 1) {
new_char = serial_getc ();
if ((new_char & 0xE0) == 0)
goto packet_error;
sum += new_char & 0xff;
--length;
if (k_state == DATA_TYPE) {
/* pass on the data if this is a data packet */
k_data_char (new_char);
} else if (k_state == SEND_TYPE) {
/* save send pack in buffer as is */
*send_ptr++ = new_char;
/* if too much data, back off the pointer */
if (send_ptr >= &send_parms[SEND_DATA_SIZE])
--send_ptr;
}
}
/* get and validate checksum character */
new_char = serial_getc ();
if ((new_char & 0xE0) == 0)
goto packet_error;
if (new_char != tochar ((sum + ((sum >> 6) & 0x03)) & 0x3f))
goto packet_error;
/* get END_CHAR */
new_char = serial_getc ();
if (new_char != END_CHAR) {
packet_error:
/* restore state machines */
k_state = k_state_saved;
k_data_restore ();
/* send a negative acknowledge packet in */
send_nack (n);
} else if (k_state == SEND_TYPE) {
/* crack the protocol parms, build an appropriate ack packet */
handle_send_packet (n);
} else {
/* send simple acknowledge packet in */
send_ack (n);
/* quit if end of transmission */
if (k_state == BREAK_TYPE)
done = 1;
}
++z;
}
return ((ulong) os_data_addr - (ulong) bin_start_address);
}
#endif /* CFG_CMD_LOADB */
#if (CONFIG_COMMANDS & CFG_CMD_HWFLOW)
int do_hwflow (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
{
extern int hwflow_onoff(int);
if (argc == 2) {
if (strcmp(argv[1], "off") == 0)
hwflow_onoff(-1);
else
if (strcmp(argv[1], "on") == 0)
hwflow_onoff(1);
else
printf("Usage: %s\n", cmdtp->usage);
}
printf("RTS/CTS hardware flow control: %s\n", hwflow_onoff(0) ? "on" : "off");
return 0;
}
#endif /* CFG_CMD_HWFLOW */