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u_gnss_private.c
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u_gnss_private.c
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/*
* Copyright 2019-2024 u-blox
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/* Only #includes of u_* and the C standard library are allowed here,
* no platform stuff and no OS stuff. Anything required from
* the platform/OS must be brought in through u_port* to maintain
* portability.
*/
/** @file
* @brief Implementation of functions that are private to GNSS.
*/
#ifdef U_CFG_OVERRIDE
# include "u_cfg_override.h" // For a customer's configuration override
#endif
#include "stddef.h" // NULL, size_t etc.
#include "stdint.h" // int32_t etc.
#include "stdbool.h"
#include "string.h" // memmove(), strstr()
#include "ctype.h"
#include "u_cfg_os_platform_specific.h"
#include "u_cfg_sw.h"
#include "u_error_common.h"
#include "u_assert.h"
#include "u_port.h"
#include "u_port_os.h"
#include "u_port_heap.h"
#include "u_port_uart.h"
#include "u_port_i2c.h"
#include "u_port_spi.h"
#include "u_port_debug.h"
#include "u_timeout.h"
#include "u_hex_bin_convert.h"
#include "u_at_client.h"
#include "u_ubx_protocol.h"
#include "u_device_shared.h"
#include "u_device_serial.h"
#include "u_network_shared.h"
#include "u_short_range_module_type.h"
#include "u_short_range.h" // For uShortRangeAtClientHandleGet()
#include "u_cell_module_type.h"
#include "u_cell.h" // For uCellAtClientHandleGet()
#include "u_gnss_module_type.h"
#include "u_gnss_type.h"
#include "u_gnss.h"
#include "u_gnss_private.h"
#include "u_gnss_msg.h"
#include "u_gnss_msg_private.h"
#include "u_gnss_cfg.h"
#include "u_gnss_cfg_val_key.h"
#include "u_gnss_cfg_private.h"
/* ----------------------------------------------------------------
* COMPILE-TIME MACROS
* -------------------------------------------------------------- */
#ifndef U_GNSS_AT_BUFFER_LENGTH_BYTES
/** The length of a temporary buffer store a hex-encoded UBX-format
* message when receiving responses over an AT interface.
*/
# define U_GNSS_AT_BUFFER_LENGTH_BYTES ((U_GNSS_MAX_UBX_PROTOCOL_MESSAGE_BODY_LENGTH_BYTES + \
U_UBX_PROTOCOL_OVERHEAD_LENGTH_BYTES) * 2)
#endif
#ifndef U_GNSS_PRIVATE_SPI_READ_LENGTH_MIN_BYTES
/** The minimum number of bytes to read on an SPI transport when
* trying to determine if there's anything valid to read.
*/
# define U_GNSS_PRIVATE_SPI_READ_LENGTH_MIN_BYTES 1
#endif
// Do some cross-checking
#if U_GNSS_PRIVATE_SPI_READ_LENGTH_MIN_BYTES > U_GNSS_DEFAULT_SPI_FILL_THRESHOLD
# error U_GNSS_PRIVATE_SPI_READ_LENGTH_MIN_BYTES must be less than or equal to U_GNSS_DEFAULT_SPI_FILL_THRESHOLD
#endif
#if U_GNSS_PRIVATE_SPI_READ_LENGTH_MIN_BYTES > U_GNSS_SPI_FILL_THRESHOLD_MAX
# error U_GNSS_PRIVATE_SPI_READ_LENGTH_MIN_BYTES must be less than or equal to U_GNSS_SPI_FILL_THRESHOLD_MAX
#endif
#if U_GNSS_DEFAULT_SPI_FILL_THRESHOLD > U_GNSS_SPI_BUFFER_LENGTH_BYTES
# error U_GNSS_DEFAULT_SPI_FILL_THRESHOLD must be less than or equal to U_GNSS_SPI_BUFFER_LENGTH_BYTES
#endif
#if U_GNSS_DEFAULT_SPI_FILL_THRESHOLD > U_GNSS_SPI_FILL_THRESHOLD_MAX
# error U_GNSS_DEFAULT_SPI_FILL_THRESHOLD must be less than or equal to U_GNSS_SPI_FILL_THRESHOLD_MAX
#endif
#ifndef U_GNSS_PRIVATE_STREAMED_POS_ENSURE_SETTINGS_RETRIES
/** Sometimes, when position has been streamed, restoring save settings
* for measurement rate and message rate can fail; this is the number
* of retries to perform when it fails.
*/
# define U_GNSS_PRIVATE_STREAMED_POS_ENSURE_SETTINGS_RETRIES 2
#endif
#ifndef U_GNSS_PRIVATE_SENT_MESSAGE_STRING
/** There is a Python script in the gnss/api directory which
* looks for the string below as a key to find the commands sent
* to the GNSS device in order to write them to a file which the
* uCenter tool can import. Should you ever change the string
* below you must change the script to match.
*/
# define U_GNSS_PRIVATE_SENT_MESSAGE_STRING "U_GNSS: sent command"
#endif
#ifndef U_GNSS_PRIVATE_RECEIVED_MESSAGE_STRING_WITH_CLASS_AND_ID
/** There is a Python script in the gnss/api directory which
* looks for the string below as a key to find the commands received
* from the GNSS device in order to write them to a file which the
* uCenter tool can import. Should you ever change the string
* below you must change the script to match.
*/
# define U_GNSS_PRIVATE_RECEIVED_MESSAGE_STRING_WITH_CLASS_AND_ID "U_GNSS: decoded UBX response 0x%02x 0x%02x"
#endif
/* ----------------------------------------------------------------
* TYPES
* -------------------------------------------------------------- */
/** Structure to hold a received UBX-format message.
*/
typedef struct {
int32_t cls;
int32_t id;
char **ppBody; /**< a pointer to a pointer that the received
message body will be written to. If *ppBody is NULL
memory will be allocated. If ppBody is NULL
then the response is not captured (but this
structure may still be used for cls/id matching). */
size_t bodySize; /**< the number of bytes of storage at *ppBody;
must be zero if ppBody is NULL or
*ppBody is NULL. If non-zero it MUST be
large enough to fit the body in or the
CRC calculation will fail. */
} uGnssPrivateUbxReceiveMessage_t;
/* ----------------------------------------------------------------
* VARIABLES THAT ARE SHARED THROUGHOUT THE GNSS IMPLEMENTATION
* -------------------------------------------------------------- */
/** Root for the linked list of instances.
*/
uGnssPrivateInstance_t *gpUGnssPrivateInstanceList = NULL;
/** Mutex to protect the linked list.
*/
uPortMutexHandle_t gUGnssPrivateMutex = NULL;
/** The characteristics of the modules supported by this driver,
* compiled into the driver. Order is important: uGnssModuleType_t
* is used to index into this array.
*/
const uGnssPrivateModule_t gUGnssPrivateModuleList[] = {
{
U_GNSS_MODULE_TYPE_M8,
(1UL << (int32_t) U_GNSS_PRIVATE_FEATURE_OLD_CFG_API) /* features */
},
{
U_GNSS_MODULE_TYPE_M9,
((1UL << (int32_t) U_GNSS_PRIVATE_FEATURE_CFGVALXXX) |
(1UL << (int32_t) U_GNSS_PRIVATE_FEATURE_OLD_CFG_API) |
(1UL << (int32_t) U_GNSS_PRIVATE_FEATURE_GEOFENCE) /* features */
)
},
{
U_GNSS_MODULE_TYPE_M10,
((1UL << (int32_t) U_GNSS_PRIVATE_FEATURE_CFGVALXXX) |
(1UL << (int32_t) U_GNSS_PRIVATE_FEATURE_RXM_MEAS_50_20_C12_D12) /* features */
)
},
// Add new module types here, before the U_GNSS_MODULE_TYPE_ANY entry (since
// the uGnssModuleType_t value is used as an index into this array).
{
U_GNSS_MODULE_TYPE_ANY,
// The module attributes set here should be such that they help
// in identifying the actual module type.
(0x00UL) /* features */
}
};
/** Number of items in the gUGnssPrivateModuleList array, has to be
* done in this file and externed or GCC complains about asking
* for the size of a partially defined type.
*/
const size_t gUGnssPrivateModuleListSize = sizeof(gUGnssPrivateModuleList) /
sizeof(gUGnssPrivateModuleList[0]);
/* ----------------------------------------------------------------
* VARIABLES
* -------------------------------------------------------------- */
/** Table to convert a GNSS transport type into a streaming transport type.
*/
static const int32_t gGnssPrivateTransportTypeToStream[] = {
U_GNSS_PRIVATE_STREAM_TYPE_NONE, // U_GNSS_TRANSPORT_NONE
U_GNSS_PRIVATE_STREAM_TYPE_UART, // U_GNSS_TRANSPORT_UART or U_GNSS_TRANSPORT_UART_1
U_ERROR_COMMON_INVALID_PARAMETER, // U_GNSS_TRANSPORT_AT
U_GNSS_PRIVATE_STREAM_TYPE_I2C, // U_GNSS_TRANSPORT_I2C
U_GNSS_PRIVATE_STREAM_TYPE_SPI, // U_GNSS_TRANSPORT_SPI
U_GNSS_PRIVATE_STREAM_TYPE_VIRTUAL_SERIAL, // U_GNSS_TRANSPORT_VIRTUAL_SERIAL
U_GNSS_PRIVATE_STREAM_TYPE_UART, // U_GNSS_TRANSPORT_UART_2
U_GNSS_PRIVATE_STREAM_TYPE_UART // U_GNSS_TRANSPORT_USB
};
/** Table to convert a port number to the UBX-CFG-VAL group ID that
* configures that port number for output protocol.
*/
static const uGnssCfgValKeyGroupId_t gPortToCfgValGroupIdOutProt[] = {
U_GNSS_CFG_VAL_KEY_GROUP_ID_I2COUTPROT, // 0: I2C
U_GNSS_CFG_VAL_KEY_GROUP_ID_UART1OUTPROT, // 1: UART/UART1
U_GNSS_CFG_VAL_KEY_GROUP_ID_UART2OUTPROT, // 2: UART/UART2
U_GNSS_CFG_VAL_KEY_GROUP_ID_USBOUTPROT, // 3: USB
U_GNSS_CFG_VAL_KEY_GROUP_ID_SPIOUTPROT // 4: SPI
};
/** Table to convert an output protocol type to the UBX-CFG-VAL item ID
* for that output protocol type.
*/
static const uint8_t gProtocolTypeToCfgValItemIdOutProt[] = {
1, // 0: U_GNSS_PROTOCOL_UBX
2, // 1: U_GNSS_PROTOCOL_NMEA
4 // 2: U_GNSS_PROTOCOL_RTCM
};
/** Table of the key IDs of the UBX-CFG-VAL group CFG-RATE.
*/
static const uint32_t gCfgValKeyIdCfgRate[] = {
U_GNSS_CFG_VAL_KEY_ID_RATE_MEAS_U2, // Measurement rate in ms
U_GNSS_CFG_VAL_KEY_ID_RATE_NAV_U2, // Navigation count
U_GNSS_CFG_VAL_KEY_ID_RATE_TIMEREF_E1 // Time system
};
/* ----------------------------------------------------------------
* STATIC FUNCTIONS: MESSAGE RELATED
* -------------------------------------------------------------- */
// Match an NMEA ID with the wanted NMEA ID. Both pointers must be
// to null-terminated strings.
static bool nmeaIdMatch(const char *pNmeaIdActual, const char *pNmeaIdWanted)
{
bool match = true;
if (pNmeaIdWanted != NULL) { // A wanted string of NULL matches anything
match = false; // An actual string of NULL matches nothing (except NULL)
if (pNmeaIdActual != NULL) {
match = true;
while ((*pNmeaIdWanted != 0) && match) {
if ((*pNmeaIdActual == 0) ||
((*pNmeaIdWanted != '?') && (*pNmeaIdWanted != *pNmeaIdActual))) {
match = false;
}
pNmeaIdActual++;
pNmeaIdWanted++;
}
}
}
return match;
}
// Match an UBX ID with the wanted UXB ID, allowing ALL wildcards 0xFF.
static bool ubxIdMatch(uint16_t ubxIdActual, uint16_t ubxIdWanted)
{
if ((ubxIdWanted & U_GNSS_UBX_MESSAGE_ID_ALL) == U_GNSS_UBX_MESSAGE_ID_ALL) {
ubxIdActual |= U_GNSS_UBX_MESSAGE_ID_ALL;
}
if ((ubxIdWanted & (U_GNSS_UBX_MESSAGE_CLASS_ALL << 8)) ==
(U_GNSS_UBX_MESSAGE_CLASS_ALL << 8)) {
ubxIdActual |= (U_GNSS_UBX_MESSAGE_CLASS_ALL << 8);
}
return ubxIdActual == ubxIdWanted;
}
// Match an RTCM ID with the wanted RTCM ID, allowing ALL wildcard 0xFFFF.
static bool rtcmIdMatch(uint16_t rtcmIdActual, uint16_t rtcmIdWanted)
{
return (rtcmIdActual == rtcmIdWanted) || (rtcmIdWanted == U_GNSS_RTCM_MESSAGE_ID_ALL);
}
#ifdef U_GNSS_PRIVATE_DEBUG_PARSING
// Print out a message ID, only used when debugging message parsing.
static void printId(uGnssPrivateMessageId_t *pId)
{
if (pId->type == U_GNSS_PROTOCOL_UBX) {
uPortLog("UBX %04x", pId->id.ubx);
} else if (pId->type == U_GNSS_PROTOCOL_NMEA) {
uPortLog("NMEA %s", pId->id.nmea);
} else if (pId->type == U_GNSS_PROTOCOL_RTCM) {
uPortLog("RTCM %d", pId->id.rtcm);
} else if (pId->type == U_GNSS_PROTOCOL_UNKNOWN) {
uPortLog("UNKNOWN");
} else {
uPortLog("ERROR");
}
}
#endif
/* ----------------------------------------------------------------
* STATIC FUNCTIONS: STREAMING TRANSPORT ONLY
* -------------------------------------------------------------- */
// Read or peek-at the data in the internal ring buffer.
static int32_t streamGetFromRingBuffer(uGnssPrivateInstance_t *pInstance,
int32_t readHandle,
char *pBuffer, size_t size,
size_t offset,
int32_t maxTimeMs,
bool andRemove)
{
int32_t errorCodeOrLength = (int32_t) U_ERROR_COMMON_INVALID_PARAMETER;
size_t receiveSize;
size_t totalSize = 0;
int32_t x;
size_t leftToRead = size;
uTimeoutStart_t timeoutStart;
if (pInstance != NULL) {
timeoutStart = uTimeoutStart();
errorCodeOrLength = (int32_t) U_ERROR_COMMON_TIMEOUT;
while ((leftToRead > 0) &&
!uTimeoutExpiredMs(timeoutStart, maxTimeMs)) {
if (andRemove) {
receiveSize = (int32_t) uRingBufferReadHandle(&(pInstance->ringBuffer),
readHandle,
pBuffer, leftToRead);
} else {
receiveSize = (int32_t) uRingBufferPeekHandle(&(pInstance->ringBuffer),
readHandle,
pBuffer, leftToRead,
offset);
offset += receiveSize;
}
leftToRead -= receiveSize;
totalSize += receiveSize;
if (pBuffer != NULL) {
pBuffer += receiveSize;
}
if (receiveSize == 0) {
x = uGnssPrivateStreamFillRingBuffer(pInstance,
U_GNSS_RING_BUFFER_MIN_FILL_TIME_MS,
maxTimeMs / 10);
if (x < 0) {
errorCodeOrLength = x;
}
}
}
if (totalSize > 0) {
errorCodeOrLength = (int32_t) totalSize;
}
}
return errorCodeOrLength;
}
// Send a message over UART or I2C or SPI.
static int32_t sendMessageStream(uGnssPrivateInstance_t *pInstance,
const char *pMessage,
size_t messageLengthBytes, bool printIt)
{
int32_t errorCodeOrSentLength = (int32_t) U_ERROR_COMMON_INVALID_PARAMETER;
int32_t privateStreamTypeOrError;
privateStreamTypeOrError = uGnssPrivateGetStreamType(pInstance->transportType);
switch (privateStreamTypeOrError) {
case U_GNSS_PRIVATE_STREAM_TYPE_UART: {
errorCodeOrSentLength = uPortUartWrite(pInstance->transportHandle.uart,
pMessage, messageLengthBytes);
}
break;
case U_GNSS_PRIVATE_STREAM_TYPE_I2C: {
errorCodeOrSentLength = uPortI2cControllerExchange(pInstance->transportHandle.i2c,
pInstance->i2cAddress,
pMessage, messageLengthBytes,
NULL, 0, false);
if (errorCodeOrSentLength == 0) {
errorCodeOrSentLength = messageLengthBytes;
}
}
break;
case U_GNSS_PRIVATE_STREAM_TYPE_SPI: {
char spiBuffer[U_GNSS_SPI_FILL_THRESHOLD_MAX] = {0}; // Zero'ed to keep Valgrind happy
size_t offset = 0;
size_t thisLength;
// In the SPI case we are always necessarily receiving while
// we send, so we have to capture that data and store it in
// our internal SPI buffer so as not to lose anything; we
// don't want to allocate another receive buffer here though,
// so we send in chunks of length up to our SPI fill-checking
// buffer ('cos it's a convenient length).
errorCodeOrSentLength = 0;
for (size_t x = 0; (offset < messageLengthBytes) && (errorCodeOrSentLength >= 0); x++) {
thisLength = messageLengthBytes - offset;
if (thisLength > U_GNSS_SPI_FILL_THRESHOLD_MAX) {
thisLength = U_GNSS_SPI_FILL_THRESHOLD_MAX;
}
errorCodeOrSentLength = uPortSpiControllerSendReceiveBlock(pInstance->transportHandle.spi,
pMessage + offset,
thisLength,
spiBuffer,
thisLength);
if (errorCodeOrSentLength > 0) {
offset += errorCodeOrSentLength;
// This will add any non-fill SPI received data to the
// internal SPI ring buffer
uGnssPrivateSpiAddReceivedData(pInstance, spiBuffer, errorCodeOrSentLength);
}
}
if (errorCodeOrSentLength >= 0) {
errorCodeOrSentLength = offset;
}
}
break;
case U_GNSS_PRIVATE_STREAM_TYPE_VIRTUAL_SERIAL: {
uDeviceSerial_t *pDeviceSerial = pInstance->transportHandle.pDeviceSerial;
if (pDeviceSerial != NULL) {
errorCodeOrSentLength = pDeviceSerial->write(pDeviceSerial,
pMessage, messageLengthBytes);
}
}
break;
default:
break;
}
if (printIt && (errorCodeOrSentLength == messageLengthBytes)) {
uPortLog(U_GNSS_PRIVATE_SENT_MESSAGE_STRING);
uGnssPrivatePrintBuffer(pMessage, messageLengthBytes);
uPortLog(".\n");
}
return errorCodeOrSentLength;
}
// Receive a UBX format message over UART or I2C or SPI.
// On entry pResponse should be set to the message class and ID of the
// expected response, wild cards permitted. On success it will
// be set to the message ID received and the UBX message body length
// will be returned.
static int32_t receiveUbxMessageStream(uGnssPrivateInstance_t *pInstance,
uGnssPrivateUbxReceiveMessage_t *pResponse,
int32_t timeoutMs, bool printIt)
{
int32_t errorCodeOrLength = 0; // Deliberate choice to return 0 if pResponse
uGnssPrivateMessageId_t privateMessageId; // indicates that no response is required
char *pBuffer = NULL;
if ((pInstance != NULL) && (pResponse != NULL) && (pResponse->ppBody != NULL)) {
// Convert uGnssPrivateUbxReceiveMessage_t into uGnssPrivateMessageId_t
privateMessageId.type = U_GNSS_PROTOCOL_UBX;
privateMessageId.id.ubx = (U_GNSS_UBX_MESSAGE_CLASS_ALL << 8) | U_GNSS_UBX_MESSAGE_ID_ALL;
if (pResponse->cls >= 0) {
privateMessageId.id.ubx = (privateMessageId.id.ubx & 0x00ff) | (uint16_t) (((
uint16_t) pResponse->cls) << 8);
}
if (pResponse->id >= 0) {
privateMessageId.id.ubx = (privateMessageId.id.ubx & 0xff00) | (uint16_t) pResponse->id;
}
// Now wait for the message, allowing a buffer to be allocated by
// the message receive function
errorCodeOrLength = uGnssPrivateReceiveStreamMessage(pInstance,
&privateMessageId,
pInstance->ringBufferReadHandlePrivate,
&pBuffer, 0,
timeoutMs, NULL);
if (errorCodeOrLength >= U_UBX_PROTOCOL_OVERHEAD_LENGTH_BYTES) {
// Convert uGnssPrivateMessageId_t into uGnssPrivateUbxReceiveMessage_t
pResponse->cls = privateMessageId.id.ubx >> 8;
pResponse->id = privateMessageId.id.ubx & 0xFF;
// Remove the protocol overhead from the length, we just want the body
errorCodeOrLength -= U_UBX_PROTOCOL_OVERHEAD_LENGTH_BYTES;
// Copy the body of the message into the response
if (*(pResponse->ppBody) == NULL) {
*(pResponse->ppBody) = (char *) pUPortMalloc(errorCodeOrLength);
} else {
if (errorCodeOrLength > (int32_t) pResponse->bodySize) {
errorCodeOrLength = (int32_t) pResponse->bodySize;
}
}
if (*(pResponse->ppBody) != NULL) {
memcpy(*(pResponse->ppBody), pBuffer + U_UBX_PROTOCOL_HEADER_LENGTH_BYTES, errorCodeOrLength);
if (printIt) {
uPortLog(U_GNSS_PRIVATE_RECEIVED_MESSAGE_STRING_WITH_CLASS_AND_ID,
privateMessageId.id.ubx >> 8, privateMessageId.id.ubx & 0xff);
if (errorCodeOrLength > 0) {
uPortLog(":");
uGnssPrivatePrintBuffer(*(pResponse->ppBody), errorCodeOrLength);
}
uPortLog(" [body %d byte(s)].\n", errorCodeOrLength);
}
} else {
errorCodeOrLength = (int32_t) U_ERROR_COMMON_NO_MEMORY;
}
} else if (printIt && (errorCodeOrLength == (int32_t) U_GNSS_ERROR_NACK)) {
uPortLog("U_GNSS: got Nack for 0x%02x 0x%02x.\n",
pResponse->cls, pResponse->id);
}
// Free memory
uPortFree(pBuffer);
}
return errorCodeOrLength;
}
/* ----------------------------------------------------------------
* STATIC FUNCTIONS: AT TRANSPORT ONLY
* -------------------------------------------------------------- */
// Send a UBX format message over an AT interface and receive
// the response. No matching of message ID or class for
// the response is performed as it is not possible to get other
// responses when using an AT command.
static int32_t sendReceiveUbxMessageAt(const uAtClientHandle_t atHandle,
const char *pSend,
size_t sendLengthBytes,
uGnssPrivateUbxReceiveMessage_t *pResponse,
int32_t timeoutMs,
bool printIt)
{
int32_t errorCodeOrLength = (int32_t) U_ERROR_COMMON_NO_MEMORY;
int32_t x;
size_t bytesToSend;
char *pBuffer;
bool bufferReuse = false;
int32_t bytesRead;
size_t captureSize;
int32_t clsNack = 0x05;
int32_t idNack = 0x00;
char ackBody[2] = {0};
bool atPrintOn = uAtClientPrintAtGet(atHandle);
bool atDebugPrintOn = uAtClientDebugGet(atHandle);
U_ASSERT(pResponse != NULL);
// Need a buffer to hex encode the message into
// and receive the response into
x = (int32_t) (sendLengthBytes * 2) + 1; // +1 for terminator
if (x < U_GNSS_AT_BUFFER_LENGTH_BYTES + 1) {
x = U_GNSS_AT_BUFFER_LENGTH_BYTES + 1;
}
pBuffer = (char *) pUPortMalloc(x);
if (pBuffer != NULL) {
errorCodeOrLength = (int32_t) U_GNSS_ERROR_TRANSPORT;
bytesToSend = uBinToHex(pSend, sendLengthBytes, pBuffer);
if (!printIt) {
// Switch off the AT command printing if we've been
// told not to print stuff; particularly important
// on platforms where the C library leaks memory
// when called from dynamically created tasks and this
// is being called for the GNSS asynchronous API
uAtClientPrintAtSet(atHandle, false);
uAtClientDebugSet(atHandle, false);
}
// Add terminator
*(pBuffer + bytesToSend) = 0;
uAtClientLock(atHandle);
uAtClientTimeoutSet(atHandle, timeoutMs);
uAtClientCommandStart(atHandle, "AT+UGUBX=");
uAtClientWriteString(atHandle, pBuffer, true);
// Read the response
uAtClientCommandStop(atHandle);
if (printIt) {
uPortLog(U_GNSS_PRIVATE_SENT_MESSAGE_STRING);
uGnssPrivatePrintBuffer(pSend, sendLengthBytes);
uPortLog(".\n");
}
uAtClientResponseStart(atHandle, "+UGUBX:");
// Read the hex-coded response back into pBuffer
bytesRead = uAtClientReadString(atHandle, pBuffer, x, false);
uAtClientResponseStop(atHandle);
if ((uAtClientUnlock(atHandle) == 0) && (bytesRead >= 0) &&
(pResponse->ppBody != NULL)) {
// Decode the hex into the same buffer
x = (int32_t) uHexToBin(pBuffer, bytesRead, pBuffer);
if (x > 0) {
// Deal with the output buffer
captureSize = x;
if (*(pResponse->ppBody) != NULL) {
if (captureSize > pResponse->bodySize) {
captureSize = pResponse->bodySize;
}
} else {
// We can just re-use the buffer we already have
*(pResponse->ppBody) = pBuffer;
bufferReuse = true;
}
errorCodeOrLength = (int32_t) captureSize;
if (captureSize > 0) {
// First check if we received a NACK
if ((uUbxProtocolDecode(pBuffer, x, &clsNack, &idNack,
ackBody, sizeof(ackBody),
NULL) == 2) &&
(ackBody[0] == pResponse->cls) &&
(ackBody[1] == pResponse->id)) {
// We got a NACK for the message class
// and ID we are monitoring
errorCodeOrLength = (int32_t) U_GNSS_ERROR_NACK;
} else {
// No NACK, we can decode the message body, noting
// that it is safe to decode back into the same buffer
errorCodeOrLength = uUbxProtocolDecode(pBuffer, x,
&(pResponse->cls),
&(pResponse->id),
*(pResponse->ppBody),
captureSize, NULL);
if (errorCodeOrLength > (int32_t) captureSize) {
errorCodeOrLength = (int32_t) captureSize;
}
}
}
if (printIt) {
if (errorCodeOrLength >= 0) {
uPortLog(U_GNSS_PRIVATE_RECEIVED_MESSAGE_STRING_WITH_CLASS_AND_ID,
pResponse->cls, pResponse->id);
if (errorCodeOrLength > 0) {
uPortLog(":");
uGnssPrivatePrintBuffer(*(pResponse->ppBody), errorCodeOrLength);
}
uPortLog(" [body %d byte(s)].\n", errorCodeOrLength);
} else if (errorCodeOrLength == (int32_t) U_GNSS_ERROR_NACK) {
uPortLog("U_GNSS: got Nack for 0x%02x 0x%02x.\n",
pResponse->cls, pResponse->id);
}
}
}
}
uAtClientPrintAtSet(atHandle, atPrintOn);
uAtClientDebugSet(atHandle, atDebugPrintOn);
if (!bufferReuse) {
uPortFree(pBuffer);
}
}
return errorCodeOrLength;
}
/* ----------------------------------------------------------------
* STATIC FUNCTIONS: ANY TRANSPORT
* -------------------------------------------------------------- */
// Send a UBX format message to the GNSS module and receive
// the response.
static int32_t sendReceiveUbxMessage(uGnssPrivateInstance_t *pInstance,
int32_t messageClass,
int32_t messageId,
const char *pMessageBody,
size_t messageBodyLengthBytes,
uGnssPrivateUbxReceiveMessage_t *pResponse)
{
int32_t errorCodeOrResponseLength = (int32_t) U_ERROR_COMMON_INVALID_PARAMETER;
int32_t privateStreamTypeOrError;
int32_t bytesToSend = 0;
char *pBuffer;
bool keepTrying = true;
if ((pInstance != NULL) &&
(((pMessageBody == NULL) && (messageBodyLengthBytes == 0)) ||
(messageBodyLengthBytes > 0)) &&
((pResponse->bodySize == 0) || (pResponse->ppBody != NULL))) {
errorCodeOrResponseLength = (int32_t) U_ERROR_COMMON_NO_MEMORY;
// Allocate a buffer big enough to encode the outgoing message
pBuffer = (char *) pUPortMalloc(messageBodyLengthBytes + U_UBX_PROTOCOL_OVERHEAD_LENGTH_BYTES);
if (pBuffer != NULL) {
errorCodeOrResponseLength = (int32_t) U_GNSS_ERROR_TRANSPORT;
bytesToSend = uUbxProtocolEncode(messageClass, messageId,
pMessageBody, messageBodyLengthBytes,
pBuffer);
if (bytesToSend > 0) {
U_PORT_MUTEX_LOCK(pInstance->transportMutex);
privateStreamTypeOrError = uGnssPrivateGetStreamType(pInstance->transportType);
if ((pResponse != NULL) && (pResponse->ppBody != NULL) &&
(privateStreamTypeOrError >= 0)) {
// For a streaming transport, if we're going to wait for
// a response, make sure that any historical data is
// cleared from our handle in the ring buffer so that
// we don't pick it up instead, and lock our read
// pointer before we do the send so that we are sure
// we won't lose the response
uGnssPrivateStreamFillRingBuffer(pInstance,
U_GNSS_RING_BUFFER_MIN_FILL_TIME_MS,
U_GNSS_RING_BUFFER_MAX_FILL_TIME_MS);
uRingBufferLockReadHandle(&(pInstance->ringBuffer),
pInstance->ringBufferReadHandlePrivate);
uRingBufferFlushHandle(&(pInstance->ringBuffer),
pInstance->ringBufferReadHandlePrivate);
}
for (int32_t x = 0; (x <= pInstance->retriesOnNoResponse) && keepTrying; x++) {
if (privateStreamTypeOrError >= 0) {
errorCodeOrResponseLength = sendMessageStream(pInstance, pBuffer, bytesToSend,
pInstance->printUbxMessages);
if (errorCodeOrResponseLength >= 0) {
errorCodeOrResponseLength = receiveUbxMessageStream(pInstance, pResponse,
pInstance->timeoutMs,
pInstance->printUbxMessages);
}
} else {
// Not a stream, we're on AT
//lint -e{1773} Suppress attempt to cast away const: I'm not!
errorCodeOrResponseLength = sendReceiveUbxMessageAt((const uAtClientHandle_t)
pInstance->transportHandle.pAt,
pBuffer, bytesToSend,
pResponse, pInstance->timeoutMs,
pInstance->printUbxMessages);
}
if ((errorCodeOrResponseLength >= 0) ||
(errorCodeOrResponseLength == (int32_t) U_GNSS_ERROR_NACK)) {
keepTrying = false;
} else if (pInstance->retriesOnNoResponse > 0) {
uPortTaskBlock(U_GNSS_RETRY_ON_NO_RESPONSE_DELAY_MS);
}
}
// Make sure the read handle is always unlocked afterwards
uRingBufferUnlockReadHandle(&(pInstance->ringBuffer), pInstance->ringBufferReadHandlePrivate);
U_PORT_MUTEX_UNLOCK(pInstance->transportMutex);
}
// Free memory
uPortFree(pBuffer);
}
}
return errorCodeOrResponseLength;
}
/* ----------------------------------------------------------------
* STATIC FUNCTIONS: MESSAGE PARSERS
* -------------------------------------------------------------- */
/** UBX Parser function.
*
* @param parseHandle the parse handle of the ring buffer to read from.
* @param[in] pUserParam the user parameter passed to uRingBufferParseHandle().
* @return negative error or success code.
*/
static int32_t parseUbx(uParseHandle_t parseHandle, void *pUserParam)
{
uGnssPrivateMessageId_t *pMsgId = (uGnssPrivateMessageId_t *) pUserParam;
uint8_t by = 0;
if (!uRingBufferGetByteUnprotected(parseHandle, &by)) {
return U_ERROR_COMMON_TIMEOUT;
}
if (0xB5 != by) {
return U_ERROR_COMMON_NOT_FOUND; // = µ, 0xB5
}
if (!uRingBufferGetByteUnprotected(parseHandle, &by)) {
return U_ERROR_COMMON_TIMEOUT;
}
if (0x62 != by) {
return U_ERROR_COMMON_NOT_FOUND; // = b
}
if (4 > uRingBufferBytesAvailableUnprotected(parseHandle)) {
return U_ERROR_COMMON_TIMEOUT;
}
uint8_t ckb = 0;
uint8_t cka = 0;
uint8_t cls, id;
uRingBufferGetByteUnprotected(parseHandle, &cls); // cls
cka += cls;
ckb += cka;
uRingBufferGetByteUnprotected(parseHandle, &id); // id
cka += id;
ckb += cka;
pMsgId->id.ubx = (uint16_t) ((((uint16_t) cls) << 8) + id);
uRingBufferGetByteUnprotected(parseHandle, &by); // len low
cka += by;
ckb += cka;
uint16_t l = by;
uRingBufferGetByteUnprotected(parseHandle, &by); // len high
cka += by;
ckb += cka;
l += (((uint16_t) by) << 8);
if (l > uRingBufferBytesAvailableUnprotected(parseHandle)) {
return U_ERROR_COMMON_TIMEOUT;
}
while (l --) {
uRingBufferGetByteUnprotected(parseHandle, &by);
cka += by;
ckb += cka;
}
cka = cka & 0xFF;
ckb = ckb & 0xFF;
if (!uRingBufferGetByteUnprotected(parseHandle, &by)) {
return U_ERROR_COMMON_TIMEOUT;
}
if (by != cka) {
return U_ERROR_COMMON_NOT_FOUND;
}
if (!uRingBufferGetByteUnprotected(parseHandle, &by)) {
return U_ERROR_COMMON_TIMEOUT;
}
if (by != ckb) {
return U_ERROR_COMMON_NOT_FOUND;
}
// We can only claim this as a UBX-format message if
// there was nothing that needed discarding first.
if (uRingBufferBytesDiscardUnprotected(parseHandle) == 0) {
pMsgId->type = U_GNSS_PROTOCOL_UBX;
}
return U_ERROR_COMMON_SUCCESS;
}
/** NMEA Parser function.
*
* @param parseHandle the parse handle of the ring buffer to read from.
* @param[in] pUserParam the user parameter passed to uRingBufferParseHandle().
* @return negative error or success code.
*/
static int32_t parseNmea(uParseHandle_t parseHandle, void *pUserParam)
{
uGnssPrivateMessageId_t *pMsgId = (uGnssPrivateMessageId_t *) pUserParam;
char ch = 0;
const char *hex = "0123456789ABCDEF";
if (!uRingBufferGetByteUnprotected(parseHandle, &ch)) {
return U_ERROR_COMMON_TIMEOUT;
}
if ('$' != ch) {
return U_ERROR_COMMON_NOT_FOUND;
}
char crc = 0;
int i = 0;
while (uRingBufferGetByteUnprotected(parseHandle, &ch)) {
crc ^= ch;
if (',' == ch) {
break;
}
if (i >= U_GNSS_NMEA_MESSAGE_MATCH_LENGTH_CHARACTERS) {
return U_ERROR_COMMON_NOT_FOUND;
}
if (('0' > ch) || ('Z' < ch) || (('9' < ch) && ('A' > ch))) {
return U_ERROR_COMMON_NOT_FOUND; // A-Z, 0-9
}
pMsgId->id.nmea[i++] = ch;
}
pMsgId->id.nmea[i] = '\0';
while (uRingBufferGetByteUnprotected(parseHandle, &ch)) {
if ((' ' > ch) || ('~' < ch)) {
return U_ERROR_COMMON_NOT_FOUND; // not in printable range 32 - 126
}
if ('*' == ch) {
break; // *
}
crc ^= ch;
}
if (!uRingBufferGetByteUnprotected(parseHandle, &ch)) {
return U_ERROR_COMMON_TIMEOUT;
}
if (hex[(crc >> 4) & 0xF] != ch) {
return U_ERROR_COMMON_NOT_FOUND;
}
if (!uRingBufferGetByteUnprotected(parseHandle, &ch)) {
return U_ERROR_COMMON_TIMEOUT;
}
if (hex[crc & 0xF] != ch) {
return U_ERROR_COMMON_NOT_FOUND;
}
if (!uRingBufferGetByteUnprotected(parseHandle, &ch)) {
return U_ERROR_COMMON_TIMEOUT;
}
if ('\r' != ch) {
return U_ERROR_COMMON_NOT_FOUND;
}
if (!uRingBufferGetByteUnprotected(parseHandle, &ch)) {
return U_ERROR_COMMON_TIMEOUT;
}
if ('\n' != ch) {
return U_ERROR_COMMON_NOT_FOUND;
}
// We can only claim this as an NMEA-format message if
// there was nothing that needed discarding first.
if (uRingBufferBytesDiscardUnprotected(parseHandle) == 0) {
pMsgId->type = U_GNSS_PROTOCOL_NMEA;
}
return U_ERROR_COMMON_SUCCESS;
}
/** RTCM Parser function.
*
* @param parseHandle the parse handle of the ring buffer to read from.
* @param[in] pUserParam the user parameter passed to uRingBufferParseHandle().
* @return negative error or success code.
*/
static int32_t parseRtcm(uParseHandle_t parseHandle, void *pUserParam)
{
uGnssPrivateMessageId_t *pMsgId = (uGnssPrivateMessageId_t *) pUserParam;
uint8_t by;
uint32_t crc = 0;
if (!uRingBufferGetByteUnprotected(parseHandle, &by)) {
return U_ERROR_COMMON_TIMEOUT;
}
if (0xD3 != by) {
return U_ERROR_COMMON_NOT_FOUND;
}
// CRC24Q check
const uint32_t _crc24qTable[] = {
/* 00 */ 0x000000, 0x864cfb, 0x8ad50d, 0x0c99f6, 0x93e6e1, 0x15aa1a, 0x1933ec, 0x9f7f17,
/* 08 */ 0xa18139, 0x27cdc2, 0x2b5434, 0xad18cf, 0x3267d8, 0xb42b23, 0xb8b2d5, 0x3efe2e,
/* 10 */ 0xc54e89, 0x430272, 0x4f9b84, 0xc9d77f, 0x56a868, 0xd0e493, 0xdc7d65, 0x5a319e,
/* 18 */ 0x64cfb0, 0xe2834b, 0xee1abd, 0x685646, 0xf72951, 0x7165aa, 0x7dfc5c, 0xfbb0a7,
/* 20 */ 0x0cd1e9, 0x8a9d12, 0x8604e4, 0x00481f, 0x9f3708, 0x197bf3, 0x15e205, 0x93aefe,
/* 28 */ 0xad50d0, 0x2b1c2b, 0x2785dd, 0xa1c926, 0x3eb631, 0xb8faca, 0xb4633c, 0x322fc7,
/* 30 */ 0xc99f60, 0x4fd39b, 0x434a6d, 0xc50696, 0x5a7981, 0xdc357a, 0xd0ac8c, 0x56e077,
/* 38 */ 0x681e59, 0xee52a2, 0xe2cb54, 0x6487af, 0xfbf8b8, 0x7db443, 0x712db5, 0xf7614e,
/* 40 */ 0x19a3d2, 0x9fef29, 0x9376df, 0x153a24, 0x8a4533, 0x0c09c8, 0x00903e, 0x86dcc5,
/* 48 */ 0xb822eb, 0x3e6e10, 0x32f7e6, 0xb4bb1d, 0x2bc40a, 0xad88f1, 0xa11107, 0x275dfc,
/* 50 */ 0xdced5b, 0x5aa1a0, 0x563856, 0xd074ad, 0x4f0bba, 0xc94741, 0xc5deb7, 0x43924c,
/* 58 */ 0x7d6c62, 0xfb2099, 0xf7b96f, 0x71f594, 0xee8a83, 0x68c678, 0x645f8e, 0xe21375,
/* 60 */ 0x15723b, 0x933ec0, 0x9fa736, 0x19ebcd, 0x8694da, 0x00d821, 0x0c41d7, 0x8a0d2c,
/* 68 */ 0xb4f302, 0x32bff9, 0x3e260f, 0xb86af4, 0x2715e3, 0xa15918, 0xadc0ee, 0x2b8c15,
/* 70 */ 0xd03cb2, 0x567049, 0x5ae9bf, 0xdca544, 0x43da53, 0xc596a8, 0xc90f5e, 0x4f43a5,
/* 78 */ 0x71bd8b, 0xf7f170, 0xfb6886, 0x7d247d, 0xe25b6a, 0x641791, 0x688e67, 0xeec29c,
/* 80 */ 0x3347a4, 0xb50b5f, 0xb992a9, 0x3fde52, 0xa0a145, 0x26edbe, 0x2a7448, 0xac38b3,
/* 88 */ 0x92c69d, 0x148a66, 0x181390, 0x9e5f6b, 0x01207c, 0x876c87, 0x8bf571, 0x0db98a,
/* 90 */ 0xf6092d, 0x7045d6, 0x7cdc20, 0xfa90db, 0x65efcc, 0xe3a337, 0xef3ac1, 0x69763a,
/* 98 */ 0x578814, 0xd1c4ef, 0xdd5d19, 0x5b11e2, 0xc46ef5, 0x42220e, 0x4ebbf8, 0xc8f703,
/* a0 */ 0x3f964d, 0xb9dab6, 0xb54340, 0x330fbb, 0xac70ac, 0x2a3c57, 0x26a5a1, 0xa0e95a,
/* a8 */ 0x9e1774, 0x185b8f, 0x14c279, 0x928e82, 0x0df195, 0x8bbd6e, 0x872498, 0x016863,
/* b0 */ 0xfad8c4, 0x7c943f, 0x700dc9, 0xf64132, 0x693e25, 0xef72de, 0xe3eb28, 0x65a7d3,
/* b8 */ 0x5b59fd, 0xdd1506, 0xd18cf0, 0x57c00b, 0xc8bf1c, 0x4ef3e7, 0x426a11, 0xc426ea,
/* c0 */ 0x2ae476, 0xaca88d, 0xa0317b, 0x267d80, 0xb90297, 0x3f4e6c, 0x33d79a, 0xb59b61,
/* c8 */ 0x8b654f, 0x0d29b4, 0x01b042, 0x87fcb9, 0x1883ae, 0x9ecf55, 0x9256a3, 0x141a58,
/* d0 */ 0xefaaff, 0x69e604, 0x657ff2, 0xe33309, 0x7c4c1e, 0xfa00e5, 0xf69913, 0x70d5e8,
/* d8 */ 0x4e2bc6, 0xc8673d, 0xc4fecb, 0x42b230, 0xddcd27, 0x5b81dc, 0x57182a, 0xd154d1,
/* e0 */ 0x26359f, 0xa07964, 0xace092, 0x2aac69, 0xb5d37e, 0x339f85, 0x3f0673, 0xb94a88,
/* e8 */ 0x87b4a6, 0x01f85d, 0x0d61ab, 0x8b2d50, 0x145247, 0x921ebc, 0x9e874a, 0x18cbb1,
/* f0 */ 0xe37b16, 0x6537ed, 0x69ae1b, 0xefe2e0, 0x709df7, 0xf6d10c, 0xfa48fa, 0x7c0401,
/* f8 */ 0x42fa2f, 0xc4b6d4, 0xc82f22, 0x4e63d9, 0xd11cce, 0x575035, 0x5bc9c3, 0xdd8538
};
#define RTCM_CRC(crc, by) (crc << 8) ^ _crc24qTable[(by ^ (crc >> 16)) & 0xff]
// CRC is over the entire message, 0xD3 included
crc = RTCM_CRC(crc, by);
if (!uRingBufferGetByteUnprotected(parseHandle, &by)) {
return U_ERROR_COMMON_TIMEOUT;
}
if ((0xFC & by) != 0) {
return U_ERROR_COMMON_NOT_FOUND;
}
uint16_t l = (uint16_t) ((by & 0x3) << 8);
crc = RTCM_CRC(crc, by);
if (!uRingBufferGetByteUnprotected(parseHandle, &by)) {
return U_ERROR_COMMON_TIMEOUT;
}
l += by;
// Length includes the two-byte message ID and the message
// body, i.e. up to the start of the 3-byte CRC, i.e.
// the total message length - 6.
if (l > uRingBufferBytesAvailableUnprotected(parseHandle) + 3) {
return U_ERROR_COMMON_TIMEOUT;
}
crc = RTCM_CRC(crc, by);
uint8_t idLo, idHi;
if (!uRingBufferGetByteUnprotected(parseHandle, &idLo)) {
return U_ERROR_COMMON_TIMEOUT;
}
l--;
crc = RTCM_CRC(crc, idLo);
if (!uRingBufferGetByteUnprotected(parseHandle, &idHi)) {
return U_ERROR_COMMON_TIMEOUT;
}
l--;
crc = RTCM_CRC(crc, idHi);
pMsgId->id.rtcm = (idHi >> 4) + (uint16_t) (idLo << 4);
while (l--) {
uRingBufferGetByteUnprotected(parseHandle, &by);
crc = RTCM_CRC(crc, by);
}