64 lines
2.1 KiB
C
64 lines
2.1 KiB
C
#ifndef PROTOCOL_MP1
|
|
#define PROTOCOL_MP1
|
|
|
|
#include <cfg/compiler.h>
|
|
#include <io/kfile.h>
|
|
|
|
// Frame sizing & checksum
|
|
#define MP1_MIN_FRAME_LENGTH 3
|
|
#define MP1_MAX_FRAME_LENGTH 200
|
|
#define MP1_CHECKSUM_INIT 0xAA
|
|
|
|
// We need to know some basic HDLC flag bytes
|
|
#define HDLC_FLAG 0x7E
|
|
#define HDLC_RESET 0x7F
|
|
#define AX25_ESC 0x1B
|
|
|
|
// Some further definitions FIXME:
|
|
#define MP1_PADDING 0x55
|
|
#define MP1_HEADER_PADDED 0x01
|
|
#define MP1_HEADER_COMPRESSION 0x02
|
|
|
|
// FIXME: describe
|
|
//static uint8_t compressedData[MP1_MAX_FRAME_LENGTH-0];
|
|
static uint8_t compressionBuffer[MP1_MAX_FRAME_LENGTH+10];
|
|
|
|
// Just a forward declaration that this struct exists
|
|
struct MP1Packet;
|
|
|
|
// The type of a callback function for passing
|
|
// back a decoded packet
|
|
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]; // FEC 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
|
|
bool fecEscape; // fec escape
|
|
} MP1;
|
|
|
|
// A struct encapsulating a network packet
|
|
typedef struct MP1Packet {
|
|
const uint8_t *data; // Pointer to the actual data in the packet
|
|
size_t dataLength; // The length of the received data
|
|
} MP1Packet;
|
|
|
|
void mp1Init(MP1 *mp1, KFile *modem, mp1_callback_t callback);
|
|
void mp1Read(MP1 *mp1, int byte);
|
|
void mp1Poll(MP1 *mp1);
|
|
void mp1Send(MP1 *mp1, const void *_buffer, size_t length);
|
|
|
|
int freeRam(void);
|
|
size_t compress(uint8_t *input, size_t length);
|
|
size_t decompress(uint8_t *input, size_t length);
|
|
|
|
#endif |