at.c

// -*- Mode: C; c-basic-offset: 8; -*-
//
// Copyright (c) 2011 Michael Smith, All Rights Reserved
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions
// are met:
//
//  o Redistributions of source code must retain the above copyright
//    notice, this list of conditions and the following disclaimer.
//  o Redistributions in binary form must reproduce the above copyright
//    notice, this list of conditions and the following disclaimer in
//    the documentation and/or other materials provided with the distribution.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
// FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
// COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
// INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
// SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
// HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
// STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
// OF THE POSSIBILITY OF SUCH DAMAGE.
//

///
/// @file	at.c
///
/// A simple AT command parser.
///

#include "radio.h"
#include "tdm.h"
#include "flash_layout.h"
#include "at.h"
#include "board.h"

#ifdef INCLUDE_AES
#include "AES/aes.h"
#endif

// canary data for ram wrap. It is in at.c as the compiler
// assigns addresses in alphabetial order and we want this at a low
// address
__pdata uint8_t pdata_canary = 0x41;

// AT command buffer
__xdata char at_cmd[AT_CMD_MAXLEN + 1];
__pdata uint8_t	at_cmd_len;

// mode flags
bool		at_mode_active;	///< if true, incoming bytes are for AT command
bool		at_cmd_ready;	///< if true, at_cmd / at_cmd_len contain valid data

// test bits
__pdata uint8_t		at_testmode;    ///< test modes enabled (AT_TEST_*)

// command handlers
static void	at_ok(void);
static void	at_error(void);
static void	at_i(void);
static void	at_s(void);
static void	at_ampersand(void);
static void	at_p(void);
static void	at_plus(void);
static void at_m(void);

#pragma save
#pragma nooverlay
void
at_input(register uint8_t c)
{
	// AT mode is active and waiting for a command
	switch (c) {
		// CR - submits command for processing
	case '\r':
		putchar('\n');
		at_cmd[at_cmd_len] = 0;
		at_cmd_ready = true;
		break;

		// backspace - delete a character
		// delete - delete a character
	case '\b':
	case '\x7f':
		if (at_cmd_len > 0) {
			putchar('\b');
			putchar(' ');
			putchar('\b');
			at_cmd_len--;
		}
		break;

		// character - add to buffer if valid
	default:
		if (at_cmd_len < AT_CMD_MAXLEN) {
			if (isprint(c)) {
				c = toupper(c);
				at_cmd[at_cmd_len++] = c;
				putchar(c);
			}
			break;
		}

		// If the AT command buffer overflows we abandon
		// AT mode and return to passthrough mode; this is
		// to minimise the risk of locking up on reception
		// of an accidental escape sequence.

		at_mode_active = 0;
		at_cmd_len = 0;
		break;
	}
}
#pragma restore

// +++ detector state machine
//
// states:
//
// wait_for_idle:	-> wait_for_plus1, count = 0 after 1s
//
// wait_for_plus:	-> wait_for_idle if char != +
//			-> wait_for_plus, count++ if count < 3
// wait_for_enable:	-> enabled after 1s
//			-> wait_for_idle if any char
//

#define	ATP_WAIT_FOR_IDLE	0
#define ATP_WAIT_FOR_PLUS1	1
#define ATP_WAIT_FOR_PLUS2	2
#define ATP_WAIT_FOR_PLUS3	3
#define ATP_WAIT_FOR_ENABLE	4

#define ATP_COUNT_1S		100	// 100 ticks of the 100Hz timer

static __pdata uint8_t	at_plus_state;
static __pdata uint8_t	at_plus_counter = ATP_COUNT_1S;

#pragma save
#pragma nooverlay
void
at_plus_detector(register uint8_t c)
{
	// If we get a character that's not '+', unconditionally
	// reset the state machine to wait-for-idle; this will
	// restart the 1S timer.
	//
	if (c != (uint8_t)'+')
		at_plus_state = ATP_WAIT_FOR_IDLE;

	// We got a plus; handle it based on our current state.
	//
	switch (at_plus_state) {

	case ATP_WAIT_FOR_PLUS1:
	case ATP_WAIT_FOR_PLUS2:
		at_plus_state++;
		break;

	case ATP_WAIT_FOR_PLUS3:
		at_plus_state = ATP_WAIT_FOR_ENABLE;
		at_plus_counter = ATP_COUNT_1S;
		break;

	default:
		at_plus_state = ATP_WAIT_FOR_IDLE;
		// FALLTHROUGH
	case ATP_WAIT_FOR_IDLE:
	case ATP_WAIT_FOR_ENABLE:
		at_plus_counter = ATP_COUNT_1S;
		break;
	}
}
#pragma restore

#pragma save
#pragma nooverlay
void
at_timer(void)
{
	// if the counter is running
	if (at_plus_counter > 0) {

		// if it reaches zero, the timeout has expired
		if (--at_plus_counter == 0) {

			// make the relevant state change
			switch (at_plus_state) {
			case ATP_WAIT_FOR_IDLE:
				at_plus_state = ATP_WAIT_FOR_PLUS1;
				break;

			case ATP_WAIT_FOR_ENABLE:
				at_mode_active = true;
				at_plus_state = ATP_WAIT_FOR_IDLE;

				// stuff an empty 'AT' command to get the OK prompt
				at_cmd[0] = 'A';
				at_cmd[1] = 'T';
				at_cmd[2] = '\0';
				at_cmd_len = 2;
				at_cmd_ready = true;
				break;
			default:
				// should never happen, but otherwise harmless
				break;
			}
		}
	}
}
#pragma restore

void
at_command(void)
{
	// require a command with the AT prefix
	if (at_cmd_ready) {
		if ((at_cmd_len >= 2) && (at_cmd[0] == 'R') && (at_cmd[1] == 'T')) {
			// remote AT command - send it to the tdm
			// system to send to the remote radio
			tdm_remote_at();
			at_cmd_len = 0;
			at_cmd_ready = false;
			return;
		}
		
		if ((at_cmd_len >= 2) && (at_cmd[0] == 'A') && (at_cmd[1] == 'T')) {

			// look at the next byte to determine what to do
			switch (at_cmd[2]) {
			case '\0':		// no command -> OK
				at_ok();
				break;
			case '&':
				at_ampersand();
				break;
			case '+':
				at_plus();
				break;
			case 'I':
				at_i();
				break;
			case 'M':
				at_m();
				break;
			case 'P':
				at_p();
				break;
			case 'O':		// O -> go online (exit command mode)
				at_plus_counter = ATP_COUNT_1S;
				at_mode_active = 0;
				break;
			case 'S':
				at_s();
				break;
			case 'Z':
				// generate a software reset
				RSTSRC |= (1 << 4);
				for (;;)
					;

			default:
				at_error();
			}
		}

		// unlock the command buffer
		at_cmd_len = 0;
		at_cmd_ready = false;
	}
}

static void
at_ok(void)
{
	printf("%s\n", "OK");
}

static void
at_error(void)
{
	printf("%s\n", "ERROR");
}

__xdata uint8_t		idx;
__xdata uint32_t	at_num;

/*
  parse a number at idx putting the result in at_num
 */
static void
at_parse_number() __reentrant
{
	register uint8_t c;

	at_num = 0;
	for (;;) {
		c = at_cmd[idx];
		if (!isdigit(c))
			break;
		at_num = (at_num * 10) + (c - '0');
		idx++;
	}
}

static void print_ID_vals(char param, uint8_t end,
                          const char *__code (*name_param)(__data enum ParamID param),
                          param_t (*get_param)(__data enum ParamID param)
                         )
{
  register enum ParamID id;
  // convenient way of showing all parameters
  for (id = 0; id < end; id++) {
    printf("%c%u:%s=%lu\n",
      param,
      (unsigned)id,
      name_param(id),
      (unsigned long)get_param(id));
  }
}

static void
at_i(void)
{
  switch (at_cmd[3]) {
  case '\0':
  case '0':
    printf("%s\n", g_banner_string);
    return;
  case '1':
    printf("%s\n", g_version_string);
    return;
  case '2':
    printf("%u\n", BOARD_ID);
    break;
  case '3':
    printf("%u\n", g_board_frequency);
    break;
  case '4':
    printf("%u\n", g_board_bl_version);
    return;
  case '5':
    print_ID_vals('S', PARAM_MAX, param_name, param_get);
    return;
  case '6':
    tdm_report_timing();
    return;
  case '7':
    tdm_show_rssi();
    return;
  default:
    at_error();
    return;
  }
}

static void
at_s(void)
{
	__pdata uint8_t		sreg;

	// get the register number first
	idx = 3;
	at_parse_number();
	sreg = at_num;
	// validate the selected sreg
	if (sreg >= PARAM_MAX) {
		at_error();
		return;
	}

	switch (at_cmd[idx]) {
	case '?':
		at_num = param_get(sreg);
		printf("%lu\n", at_num);
		return;

	case '=':
		if (sreg > 0) {
			idx++;
			at_parse_number();
			if (param_set(sreg, at_num)) {
				at_ok();
				return;
			}
		}
		break;
	}
	at_error();
}

static void
at_ampersand(void)
{
	switch (at_cmd[3]) {
	case 'F':
		param_default();
		at_ok();
		break;
	case 'W':
		param_save();
		at_ok();
		break;

	case 'U':
		if (!strcmp(at_cmd + 4, "PDATE")) {
			// Erase Flash signature forcing it into reprogram mode next reset
			FLKEY = 0xa5;
			FLKEY = 0xf1;
			PSCTL = 0x03;				// set PSWE and PSEE
			*(uint8_t __xdata *)FLASH_SIGNATURE_BYTES = 0xff;	// do the page erase
			PSCTL = 0x00;				// disable PSWE/PSEE
			
			// Reset the device using sofware reset
			RSTSRC |= 0x10;
			
			for (;;)
				;
		}
		at_error();
		break;

	case 'P':
		tdm_change_phase();
		break;

	case 'T':
		// enable test modes
		if (!strcmp(at_cmd + 4, "")) {
			// disable all tests
			at_testmode = 0;
		} else if (!strcmp(at_cmd + 4, "=RSSI")) {
			// display RSSI stats
			at_testmode ^= AT_TEST_RSSI;
		} else if (!strcmp(at_cmd + 4, "=TDM")) {
			// display TDM debug
			at_testmode ^= AT_TEST_TDM;
		} else {
			at_error();
		}
		break;
#ifdef INCLUDE_AES
  case 'E':
    switch (at_cmd[4]) {
      case '?':
        print_encryption_key();
        return;
        
      case '=':
        if (param_set_encryption_key((__xdata unsigned char *)&at_cmd[5])) {
          at_ok();
          return;
        }
        break;
    }
#endif // INCLUDE_AES
	default:
		at_error();
		break;
	}
}

static void
at_p (void)
{
#if PIN_MAX > 0
	__pdata uint8_t pinId;
	if(at_cmd[3] == 'P')
	{
		for (pinId = 0; pinId < PIN_MAX; pinId++)
		{
			printf("Pin:%u ", pinId);
			if (pins_user_get_io(pinId))
				printf("Output ");
			else
				printf("Input  ");
			printf("Val: %u\n",pins_user_get_value(pinId));
		}
		return;
	}
	else if(at_cmd[4] != '=' || !isdigit(at_cmd[5]))
	{
		at_error();
		return;
	}
	
	pinId = at_cmd[5] - '0';
	
	switch (at_cmd[3]) {
			
			// Set pin to output, turn mirroring off pulling pin to ground
		case 'O':
			pins_user_set_io(pinId, PIN_OUTPUT);
			break;
			
			// Need to figure out how to set pins to Input/Output
		case 'I':
			pins_user_set_io(pinId, PIN_INPUT);
			break;
			
		case 'R':
			if(pins_user_get_io(pinId) == PIN_INPUT)
				printf("val:%u\n", pins_user_get_adc(pinId));
			else
				at_error();
			return;
			break;
			
		case 'C':
			if(!isdigit(at_cmd[7]) || !pins_user_set_value(pinId, (at_cmd[7]-'0')?1:0))
			{
				at_error();
				return;
			}
			break;
		default:
			at_error();
			return;
	}
	
	at_ok();
#else
	at_error();
#endif
}

static void
at_plus(void)
{
  __pdata uint8_t		creg;
  
  // get the register number first
  idx = 4;
  at_parse_number();
  creg = at_num;
  
  switch (at_cmd[3])
  {
#if defined BOARD_rfd900a || defined BOARD_rfd900p
  case 'P': // AT+P=x set power level pwm to x immediately
    if (at_cmd[4] != '=')
    {
      break;
    }
    idx = 5;
    at_parse_number();
    PCA0CPH0 = at_num & 0xFF;
    radio_set_diversity(DIVERSITY_DISABLED);
    at_ok();
    return;
  case 'C': // AT+Cx=y write calibration value
    switch (at_cmd[idx])
    {
    case '?':
      at_num = calibration_get(creg);
      printf("%lu\n",at_num);
      return;
    case '=':
      idx++;
      at_parse_number();
      if (calibration_set(creg, at_num&0xFF))
      {
        at_ok();
      } else {
        at_error();
      }
      return;
    }
    break;
  case 'F': // AT+Fx? get calibration value
    switch (at_cmd[idx])
    {
    case '?':
      at_num = calibration_force_get(creg);
      printf("%lu\n",at_num);
      return;
    }
    break;
  case 'L': // AT+L lock bootloader area if all calibrations written
    if (calibration_lock())
    {
      at_ok();
    } else {
      at_error();
    }
    return;
#endif //BOARD_rfd900a / BOARD_rfd900p
#ifdef RFD900_DIVERSITY
  case 'A':
    if (at_cmd[4] != '=')
    {
      break;
    }
    idx = 5;
    at_parse_number();
    if (at_num == 1) {
      radio_set_diversity(DIVERSITY_ANT1);
    }
    else {
      radio_set_diversity(DIVERSITY_ANT2);
    }
    at_ok();
    return;
#endif // RFD900_DIVERSITY
  }
  at_error();
}

static void
at_m(void)
{
#ifdef BOARD_mro900
	//mRo Options
	__pdata uint8_t mRo_num = 0;
	__pdata uint8_t osc_val = 0;

	printf(" mRo command received \n");
	
	if (at_cmd[4] == '=')
	{
		idx = 5;
		at_parse_number();
		mRo_num = at_num;
		// printf("Received value: %u \n", mRo_num);
	}

	switch (at_cmd[3])
	{
	case 'H': //ATMH , HELP
		printf("mRo AT commands help \n");
		// printf("ATMO=X  ->Set oscillator capacitance. \n");
		// printf("ATMO?   ->Get Cal stored. \n");
		// printf("ATMOS   ->Store Cal in flash.\n");
		// printf("ATMOF   ->Force get Cal \n");
		// printf("ATMOL   ->Lock Bootloader with calibration \n");
		printf("ATMD=X	-> sets antenna diversity behavior \n");
		printf("     0	= diversity disabled, using antenna 1 \n");
		printf("     1	= diversity enabled \n");
		printf("     2	= diversity disabled, using antenna 2 \n");
		// printf("ATML=X	-> sets LNA \n");
		// printf("     0	= LNA disabled \n");
		// printf("     1	= LNA enabled \n");
		printf("ATMR     ->Reboot \n");
		break;
	case 'C': //ATMC
		radio_set_output_clock_freq();
		break;
	case 'O': //ATMO
		switch (at_cmd[4])
		{
			case '=': //ATMO=??
				radio_set_oscillator_capacitance(mRo_num);
				printf("OSC Value set to 0x%x | %d \n", mRo_num, mRo_num);
				return;
			case '?': //ATMO?
				osc_val = calibration_get();
				printf(" OSC value 0x%x | %d\n", osc_val, osc_val);
				if ( osc_val == 0xFF || osc_val == 0) {
					printf(" Default value 0x%x | %d\n", EZRADIOPRO_OSC_CAP_VALUE, EZRADIOPRO_OSC_CAP_VALUE);
				}
				return;
			case 'S': //ATMOS??
				// printf(" Capacitance value 0x%x | %d\n", radio_get_oscillator_capacitance(), radio_get_oscillator_capacitance());
				if (calibration_set(radio_get_oscillator_capacitance()))
				{
					at_ok();
				} else {
					printf("Calibration seems to be locked! \n");
					at_error();
				}
				return;
			case 'F': //ATMOF get calibration value
				osc_val = calibration_force_get();
				printf("%d\n", osc_val);
				return;
			case 'L': // ATMOL lock bootloader area if calibration written
				if (calibration_lock())
				{
					at_ok();
				} else {
					at_error();
				}
				return;
			default:
				at_error();
				return;
		}	
		break;

	case 'D': //ATMD=?
		if (at_cmd[4] != '=' )
		{
			at_error();
			return;
		}
		switch (mRo_num)
		{
		case 0:
			radio_set_diversity(DIVERSITY_DISABLED); //Diversity Disabled
			printf("mRo Diversity Disabled (Using Ant1) \n");
			return;
		case 1:
			radio_set_diversity(DIVERSITY_ENABLED); //Diversity Enabled
			printf("mRo Diversity Enabled \n");
			return;
		case 2:
			radio_set_diversity(DIVERSITY_ANT2); //Diversity
			printf("mRo Diversity Disabled (Using Ant2) \n");
			return;
		default:
			at_error();
			return;
		}
		break;

	case 'L': //ATML=?
		if (at_cmd[4] != '=')
		{
			at_error();
			return;
		}
		switch (mRo_num)
		{
		case 0:
			LNA_ENABLE = LNA_OFF;
			printf("mRo LNA disabled \n");
			return;
		case 1:
			LNA_ENABLE = LNA_ON;
			printf("mRo LNA enabled \n");
			return;
		default:
			at_error();
			return;
		}
	case 'R': //Software reset.
		printf("Rebooting \n");
		RSTSRC |= 0x10;
		while (1)
		{}
		break; 

	default:
		at_error();
		return;

	}
#endif
}