// Load the variable from EEPROM, if supported
//
bool AP_Param::load(void)
{
uint32_t group_element = 0;
const struct GroupInfo *ginfo;
uint8_t idx;
const struct AP_Param::Info *info = find_var_info(&group_element, &ginfo, &idx);
if (info == NULL) {
// we don't have any info on how to load it
return false;
}
struct Param_header phdr;
// create the header we will use to match the variable
if (ginfo != NULL) {
phdr.type = PGM_UINT8(&ginfo->type);
} else {
phdr.type = PGM_UINT8(&info->type);
}
phdr.key = PGM_UINT8(&info->key);
phdr.group_element = group_element;
// scan EEPROM to find the right location
uint16_t ofs;
if (!scan(&phdr, &ofs)) {
// if the value isn't stored in EEPROM then set the default value
if (ginfo != NULL) {
uintptr_t base = PGM_POINTER(&info->ptr);
set_value((enum ap_var_type)phdr.type, (void*)(base + PGM_UINT16(&ginfo->offset)),
PGM_FLOAT(&ginfo->def_value));
} else {
set_value((enum ap_var_type)phdr.type, (void*)PGM_POINTER(&info->ptr), PGM_FLOAT(&info->def_value));
}
return false;
}
if (phdr.type != AP_PARAM_VECTOR3F && idx != 0) {
// only vector3f can have non-zero idx for now
return false;
}
AP_Param *ap;
ap = this;
if (idx != 0) {
ap = (AP_Param *)((uintptr_t)ap) - (idx*sizeof(float));
}
// found it
_storage.read_block(ap, ofs+sizeof(phdr), type_size((enum ap_var_type)phdr.type));
return true;
}
/*
find a default value given a pointer to a default value in flash
*/
float AP_Param::get_default_value(const float *def_value_ptr)
{
for (uint16_t i=0; i<num_param_overrides; i++) {
if (def_value_ptr == param_overrides[i].def_value_ptr) {
return param_overrides[i].value;
}
}
return PGM_FLOAT(def_value_ptr);
}
// load default values for all scalars in a sketch. This does not
// recurse into sub-objects
void AP_Param::setup_sketch_defaults(void)
{
setup();
for (uint8_t i=0; i<_num_vars; i++) {
uint8_t type = PGM_UINT8(&_var_info[i].type);
if (type <= AP_PARAM_FLOAT) {
void *ptr = (void*)PGM_POINTER(&_var_info[i].ptr);
set_value((enum ap_var_type)type, ptr, PGM_FLOAT(&_var_info[i].def_value));
}
}
}
// load default values for all scalars in a sketch. This does not
// recurse into sub-objects
void AP_Param::setup_sketch_defaults(void)
{
setup();
for (uint8_t i=0; i<_num_vars; i++) {
uint8_t type = PGM_UINT8(&_var_info[i].type);//返回参数类型，强制转换为uint8，包括PARAM_NONE等
if (type <= AP_PARAM_FLOAT) {//按道理讲uint8_t一定会小于float，这里可能是保护的作用？？
void *ptr = (void*)PGM_POINTER(&_var_info[i].ptr);//返回指向参数在内存中位置的指针
set_value((enum ap_var_type)type, ptr, PGM_FLOAT(&_var_info[i].def_value));//把参数变量设为一个特定的值
}
}
}
// load default values for scalars in a group. This does not recurse
// into other objects. This is a static function that should be called
// in the objects constructor
void AP_Param::setup_object_defaults(const void *object_pointer, const struct GroupInfo *group_info)
{
uintptr_t base = (uintptr_t)object_pointer;
uint8_t type;
for (uint8_t i=0;
(type=PGM_UINT8(&group_info[i].type)) != AP_PARAM_NONE;
i++) {
if (type <= AP_PARAM_FLOAT) {
void *ptr = (void *)(base + PGM_UINT16(&group_info[i].offset));
set_value((enum ap_var_type)type, ptr, PGM_FLOAT(&group_info[i].def_value));
}
}
}
// Save the variable to EEPROM, if supported
//
bool AP_Param::save(void)
{
uint32_t group_element = 0;
const struct GroupInfo *ginfo;
uint8_t idx;
const struct AP_Param::Info *info = find_var_info(&group_element, &ginfo, &idx);
const AP_Param *ap;
if (info == NULL) {
// we don't have any info on how to store it
return false;
}
struct Param_header phdr;
// create the header we will use to store the variable
if (ginfo != NULL) {
phdr.type = PGM_UINT8(&ginfo->type);
} else {
phdr.type = PGM_UINT8(&info->type);
}
phdr.key = PGM_UINT8(&info->key);
phdr.group_element = group_element;
ap = this;
if (phdr.type != AP_PARAM_VECTOR3F && idx != 0) {
// only vector3f can have non-zero idx for now
return false;
}
if (idx != 0) {
ap = (const AP_Param *)((uintptr_t)ap) - (idx*sizeof(float));
}
// scan EEPROM to find the right location
uint16_t ofs;
if (scan(&phdr, &ofs)) {
// found an existing copy of the variable
eeprom_write_check(ap, ofs+sizeof(phdr), type_size((enum ap_var_type)phdr.type));
return true;
}
if (ofs == (uint16_t) ~0) {
return false;
}
// if the value is the default value then don't save
if (phdr.type <= AP_PARAM_FLOAT) {
float v1 = cast_to_float((enum ap_var_type)phdr.type);
float v2;
if (ginfo != NULL) {
v2 = PGM_FLOAT(&ginfo->def_value);
} else {
v2 = PGM_FLOAT(&info->def_value);
}
if (v1 == v2) {
return true;
}
if (phdr.type != AP_PARAM_INT32 &&
(fabsf(v1-v2) < 0.0001f*fabsf(v1))) {
// for other than 32 bit integers, we accept values within
// 0.01 percent of the current value as being the same
return true;
}
}
if (ofs+type_size((enum ap_var_type)phdr.type)+2*sizeof(phdr) >= _eeprom_size) {
// we are out of room for saving variables
return false;
}
// write a new sentinal, then the data, then the header
write_sentinal(ofs + sizeof(phdr) + type_size((enum ap_var_type)phdr.type));
eeprom_write_check(ap, ofs+sizeof(phdr), type_size((enum ap_var_type)phdr.type));
eeprom_write_check(&phdr, ofs, sizeof(phdr));
return true;
}
