flipperzero-firmware/lib/toolbox/manchester-decoder.c
あく 5209701add
[FL-1991] Rewrite flash driver (#813)
* Toolbox: fix null pointer dereference in manchester decoder.
* FuriHal: use MPU to protect from null pointer dereference, replace flash driver with our own implementation.
2021-11-10 12:53:00 +03:00

35 lines
986 B
C

#include "manchester-decoder.h"
#include <stdint.h>
static const uint8_t transitions[] = {0b00000001, 0b10010001, 0b10011011, 0b11111011};
static const ManchesterState manchester_reset_state = ManchesterStateMid1;
bool manchester_advance(
ManchesterState state,
ManchesterEvent event,
ManchesterState* next_state,
bool* data) {
bool result = false;
ManchesterState new_state;
if(event == ManchesterEventReset) {
new_state = manchester_reset_state;
} else {
new_state = transitions[state] >> event & 0x3;
if(new_state == state) {
new_state = manchester_reset_state;
} else {
if(new_state == ManchesterStateMid0) {
if (data) *data = false;
result = true;
} else if(new_state == ManchesterStateMid1) {
if (data) *data = true;
result = true;
}
}
}
*next_state = new_state;
return result;
}