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TCP mode

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This commit is contained in:
Mark Qvist 2014-04-28 17:47:32 +02:00
parent 8ba0ce4fad
commit f960709e82
10 changed files with 131 additions and 268 deletions
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4
Modem/config.h
View file

@ -19,7 +19,7 @@
#define CONFIG_AFSK_RXTIMEOUT 0 // How long a read operation from the modem
// will wait for data before timing out.
#define CONFIG_AFSK_PREAMBLE_LEN 550UL // The length of the packet preamble in milliseconds
#define CONFIG_AFSK_TRAILER_LEN 10UL // The length of the packet tail in milliseconds
#define CONFIG_AFSK_PREAMBLE_LEN 400UL // The length of the packet preamble in milliseconds
#define CONFIG_AFSK_TRAILER_LEN 50UL // The length of the packet tail in milliseconds
#endif

1
Modem/hardware.c
View file

@ -114,7 +114,6 @@ void hw_afsk_adcInit(int ch, Afsk *_modem)
bool hw_ptt_on;
bool hw_afsk_dac_isr;
DECLARE_ISR(ADC_vect) {
TIFR1 = BV(ICF1);
// Call the routine for analysing the captured sample

48
Modem/main.c
View file

@ -4,7 +4,6 @@
//////////////////////////////////////////////////////
#include <cpu/irq.h> // Interrupt functionality from BertOS
#include "cfg/debug.h" // Debug configuration from BertOS
#include <drv/ser.h> // Serial driver from BertOS
#include <drv/timer.h> // Timer driver from BertOS
@ -15,6 +14,10 @@
#include "afsk.h" // Header for AFSK modem
#include "protocol/mp1.h" // Header for MP.1 protocol
#if SERIAL_DEBUG
#include "cfg/debug.h" // Debug configuration from BertOS
#endif
//////////////////////////////////////////////////////
// A few definitions //
@ -34,6 +37,7 @@ static int sbyte; // For holding byte read from serial port
static size_t serialLen = 0; // Counter for counting length of data from serial
static bool sertx = false; // Flag signifying whether it's time to send data
// Received on the serial port.
#define SER_BUFFER_FULL (serialLen < MP1_MAX_DATA_SIZE-1)
//////////////////////////////////////////////////////
// And here comes the actual program :) //
@ -85,6 +89,7 @@ int main(void)
init();
// Record the current tick count for time-keeping
ticks_t start = timer_clock();
ticks_t frameQueued = 0;
// Go into ye good ol' infinite loop
while (1)
@ -106,7 +111,7 @@ int main(void)
// If SERIAL_DEBUG is specified we'll handle
// serial data as direct human input and only
// transmit when we get a LF character
if (SERIAL_DEBUG) {
#if SERIAL_DEBUG
// If we have not yet surpassed the maximum frame length
// and the byte is not a "transmit" (newline) character,
// we should store it for transmission.
@ -121,7 +126,7 @@ int main(void)
// transmission flag to true.
sertx = true;
}
} else {
#else
// Otherwise we assume the modem is running
// in automated mode, and we push out data
// as it becomes available. We either transmit
@ -143,7 +148,7 @@ int main(void)
}
start = timer_clock();
}
#endif
} else {
if (!SERIAL_DEBUG && serialLen > 0 && timer_clock() - start > ms_to_ticks(TX_MAXWAIT)) {
sertx = true;
@ -151,17 +156,36 @@ int main(void)
}
// Check whether we should send data in our serial buffer
if (sertx) {
// Wait until incoming packets are done
if (!mp1CarrierSense(&mp1)) {
// And then send the data
mp1Send(&mp1, serialBuffer, serialLen);
// Reset the transmission flag and length counter
if (sertx) {
#if MP1_USE_TX_QUEUE
mp1QueueFrame(&mp1, serialBuffer, serialLen);
frameQueued = timer_clock();
sertx = false;
serialLen = 0;
}
#else
// Wait until incoming packets are done
if (!mp1CarrierSense(&mp1)) {
// And then send the data
mp1Send(&mp1, serialBuffer, serialLen);
// Reset the transmission flag and length counter
sertx = false;
serialLen = 0;
}
#endif
}
#if MP1_USE_TX_QUEUE
// We first wait a little to see if more
// frames are coming in.
if (timer_clock() - frameQueued > ms_to_ticks(MP1_QUEUE_TX_WAIT)) {
if (!ser_available(&ser) && !mp1CarrierSense(&mp1)) {
// And if not, we send process the frame
// queue if possible.
mp1ProcessQueue(&mp1);
}
}
#endif
}
return 0;
}

69
Modem/protocol/mp1.c
View file

@ -125,7 +125,6 @@ static void mp1Decode(MP1 *mp1) {
////////////////////////////////////////////////////////////
void mp1Poll(MP1 *mp1) {
int byte; // A place to store our read byte
sendParityBlock = false; // Reset our parity tx indicator
// Read bytes from the modem until we reach EOF
while ((byte = kfile_getc(mp1->modem)) != EOF) {
@ -263,7 +262,9 @@ void mp1Poll(MP1 *mp1) {
// corrected bytes.
mp1->checksum_in ^= a;
mp1->checksum_in ^= b;
// DEL kprintf("wt %d %c\n", mp1->packetLength-(MP1_DATA_BLOCK_SIZE)+((i/3)*2), a);
mp1->buffer[mp1->packetLength-(MP1_DATA_BLOCK_SIZE)+((i/3)*2)] = a;
// DEL kprintf("wt %d %c\n", mp1->packetLength-(MP1_DATA_BLOCK_SIZE-1)+((i/3)*2), b);
mp1->buffer[mp1->packetLength-(MP1_DATA_BLOCK_SIZE-1)+((i/3)*2)] = b;
}
@ -340,7 +341,7 @@ void mp1Poll(MP1 *mp1) {
// Now let's get to the actual reading of the data
if (mp1->reading) {
if (mp1->packetLength < MP1_MAX_FRAME_LENGTH) {
if (mp1->packetLength < MP1_MAX_FRAME_LENGTH + MP1_INTERLEAVE_SIZE) {
// If the length of the current incoming frame is
// still less than our max length, put the incoming
// byte in the buffer. When we have collected 3
@ -389,6 +390,7 @@ static void mp1WriteByte(MP1 *mp1, uint8_t byte) {
// be 3 bytes long due to the added parity
// byte.
static void mp1Putbyte(MP1 *mp1, uint8_t byte) {
// DEL kprintf("wb %c\n", byte);
mp1Interleave(mp1, byte);
if (sendParityBlock) {
@ -404,11 +406,16 @@ static void mp1Putbyte(MP1 *mp1, uint8_t byte) {
// to be transmitted, and structures it into
// a valid packet.
void mp1Send(MP1 *mp1, void *_buffer, size_t length) {
// Reset our parity tx indicator
sendParityBlock = false;
// Open transmitter and wait for MP1_TXDELAY msecs
AFSK_HW_PTT_ON();
ticks_t start = timer_clock();
while (timer_clock() - start < ms_to_ticks(MP1_TXDELAY)) {
cpu_relax();
if (!mp1->queueProcessing) {
while (timer_clock() - start < ms_to_ticks(MP1_TXDELAY)) {
cpu_relax();
}
}
// Get the transmit data buffer
@ -527,21 +534,29 @@ void mp1Send(MP1 *mp1, void *_buffer, size_t length) {
kfile_putc(HDLC_FLAG, mp1->modem);
// Turn off manual PTT
AFSK_HW_PTT_OFF();
if (!mp1->queueProcessing) AFSK_HW_PTT_OFF();
}
// This function will simply initialize
// the protocol context and allocate the
// needed memory.
void mp1Init(MP1 *mp1, KFile *modem, mp1_callback_t callback) {
// Allocate memory for our protocol "object"
memset(mp1, 0, sizeof(*mp1));
// Set references to our modem "object" and
// a callback for when a packet has been decoded
mp1->modem = modem;
mp1->callback = callback;
mp1->settleTimer = timer_clock();
mp1->randomSeed = 0;
// This function accepts a frame and stores
// it in the transmission queue
void mp1QueueFrame(MP1 *mp1, void *_buffer, size_t length) {
if (mp1->queueLength < MP1_TX_QUEUE_LENGTH) {
uint8_t *buffer = (uint8_t *)_buffer;
mp1->frameLengths[mp1->queueLength] = length;
memcpy(mp1->frameQueue[mp1->queueLength++], buffer, length);
}
}
// This function processes the transmission
// queue.
void mp1ProcessQueue(MP1 *mp1) {
int i = 0;
while (mp1->queueLength) {
mp1Send(mp1, mp1->frameQueue[i], mp1->frameLengths[i]);
i++;
mp1->queueLength--;
}
AFSK_HW_PTT_OFF();
}
// A simple form of P-persistent CSMA.
@ -563,7 +578,7 @@ bool mp1CarrierSense(MP1 *mp1) {
if (r < MP1_P_PERSISTENCE) {
return false;
} else {
mp1->settleTimer = timer_clock();
mp1->settleTimer = timer_clock() - MP1_SETTLE_TIME + MP1_SLOT_TIME;
return true;
}
} else {
@ -574,6 +589,24 @@ bool mp1CarrierSense(MP1 *mp1) {
}
}
// This function will simply initialize
// the protocol context and allocate the
// needed memory.
void mp1Init(MP1 *mp1, KFile *modem, mp1_callback_t callback) {
// Allocate memory for our protocol "object"
memset(mp1, 0, sizeof(*mp1));
// Set references to our modem "object" and
// a callback for when a packet has been decoded
mp1->modem = modem;
mp1->callback = callback;
mp1->settleTimer = timer_clock();
mp1->randomSeed = 0;
#if MP1_USE_TX_QUEUE
mp1->queueLength = 0;
mp1->queueProcessing = false;
#endif
}
// A handy debug function that can determine
// how much available memory we have left.
#if SERIAL_DEBUG

59
Modem/protocol/mp1.h
View file

@ -5,7 +5,10 @@
#include <io/kfile.h>
// Options
#define MP1_ENABLE_COMPRESSION false
#define MP1_ENABLE_TCP_COMPATIBILITY true
#if MP1_ENABLE_TCP_COMPATIBILITY
#define MP1_ENABLE_COMPRESSION false
#endif
#define MP1_ENABLE_CSMA true
// Frame sizing & checksum
@ -13,7 +16,10 @@
#if MP1_ENABLE_COMPRESSION
#define MP1_MAX_FRAME_LENGTH 22 * MP1_INTERLEAVE_SIZE
#else
#define MP1_MAX_FRAME_LENGTH 56 * MP1_INTERLEAVE_SIZE
#define MP1_MAX_FRAME_LENGTH 25 * MP1_INTERLEAVE_SIZE
#define MP1_USE_TX_QUEUE true
#define MP1_TX_QUEUE_LENGTH 2
#define MP1_QUEUE_TX_WAIT 16UL
#endif
#define MP1_HEADER_SIZE 1
#define MP1_CHECKSUM_SIZE 1
@ -24,9 +30,10 @@
// These two parameters are used for
// P-persistent CSMA
#define MP1_SETTLE_TIME 250UL // The minimum wait time before considering sending
#define MP1_P_PERSISTENCE 64UL // The probability (between 0 and 255) for sending
#define MP1_TXDELAY 0UL // Delay between turning on the transmitter and sending
#define MP1_SETTLE_TIME 175UL // The minimum wait time before considering sending
#define MP1_SLOT_TIME 100UL // The time to wait if deciding not to send
#define MP1_P_PERSISTENCE 85UL // The probability (between 0 and 255) for sending
#define MP1_TXDELAY 0UL // Delay between turning on the transmitter and sending
// We need to know some basic HDLC flag bytes
#define HDLC_FLAG 0x7E
@ -50,23 +57,29 @@ typedef void (*mp1_callback_t)(struct MP1Packet *packet);
// Struct for a protocol context
typedef struct MP1 {
uint8_t buffer[MP1_MAX_FRAME_LENGTH]; // A buffer for incoming packets
uint8_t fecBuffer[3]; // Forward Error Correction buffer
KFile *modem; // KFile access to the modem
size_t packetLength; // Counter for received packet length
size_t readLength; // This is the full read length, including parity bytes
uint8_t calculatedParity; // Calculated parity for incoming data block
mp1_callback_t callback; // The function to call when a packet has been received
uint8_t checksum_in; // Rolling checksum for incoming packets
uint8_t checksum_out; // Rolling checksum for outgoing packets
bool reading; // True when we have seen a HDLC flag
bool escape; // We need to know if we are in an escape sequence
ticks_t settleTimer; // Timer used for carrier sense settling
long correctionsMade; // A counter for how many corrections were made to a packet
uint8_t interleaveCounter; // Keeps track of when we have received an entire interleaved block
uint8_t interleaveOut[MP1_INTERLEAVE_SIZE]; // A buffer for interleaving bytes before they are sent
uint8_t interleaveIn[MP1_INTERLEAVE_SIZE]; // A buffer for storing interleaved bytes before they are deinterleaved
uint8_t randomSeed; // A seed for the pseudo-random number generator
uint8_t buffer[MP1_MAX_FRAME_LENGTH+MP1_INTERLEAVE_SIZE]; // A buffer for incoming packets
KFile *modem; // KFile access to the modem
size_t packetLength; // Counter for received packet length
size_t readLength; // This is the full read length, including parity bytes
uint8_t calculatedParity; // Calculated parity for incoming data block
mp1_callback_t callback; // The function to call when a packet has been received
uint8_t checksum_in; // Rolling checksum for incoming packets
uint8_t checksum_out; // Rolling checksum for outgoing packets
bool reading; // True when we have seen a HDLC flag
bool escape; // We need to know if we are in an escape sequence
ticks_t settleTimer; // Timer used for carrier sense settling
long correctionsMade; // A counter for how many corrections were made to a packet
uint8_t interleaveCounter; // Keeps track of when we have received an entire interleaved block
uint8_t interleaveOut[MP1_INTERLEAVE_SIZE]; // A buffer for interleaving bytes before they are sent
uint8_t interleaveIn[MP1_INTERLEAVE_SIZE]; // A buffer for storing interleaved bytes before they are deinterleaved
uint8_t randomSeed; // A seed for the pseudo-random number generator
#if MP1_USE_TX_QUEUE
bool queueProcessing; // For sending queued frames without preamble after first one
size_t queueLength; // The length of the transmission queue
size_t frameLengths[MP1_TX_QUEUE_LENGTH]; // The lengths of the frames in the queue
uint8_t frameQueue[MP1_TX_QUEUE_LENGTH] // A buffer for a queued frame
[MP1_MAX_DATA_SIZE];
#endif
} MP1;
// A struct encapsulating a network packet
@ -80,6 +93,8 @@ void mp1Init(MP1 *mp1, KFile *modem, mp1_callback_t callback);
void mp1Read(MP1 *mp1, int byte);
void mp1Poll(MP1 *mp1);
void mp1Send(MP1 *mp1, void *_buffer, size_t length);
void mp1QueueFrame(MP1 *mp1, void *_buffer, size_t length);
void mp1ProcessQueue(MP1 *mp1);
bool mp1CarrierSense(MP1 *mp1);
int freeRam(void);