libs/RFID.MFRC522
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Improve hardware based reset

Browse Source
This commit is contained in:
Rotzbua
2018-10-10 15:03:21 +02:00
committed by GitHub
parent 1cf133cb67
commit 3592862bcb
1 changed files with 2 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

2
src/MFRC522.cpp
View File

@@ -204,6 +204,8 @@ void MFRC522::PCD_Init() {
if (digitalRead(_resetPowerDownPin) == LOW) { // The MFRC522 chip is in power down mode. if (digitalRead(_resetPowerDownPin) == LOW) { // The MFRC522 chip is in power down mode.
pinMode(_resetPowerDownPin, OUTPUT); // Now set the resetPowerDownPin as digital output. pinMode(_resetPowerDownPin, OUTPUT); // Now set the resetPowerDownPin as digital output.
digitalWrite(_resetPowerDownPin, LOW); // Make shure we have a clean LOW state.
delayMicroseconds(2); // 8.8.1 Reset timing requirements says about 100ns. Let us be generous: 2μsl
digitalWrite(_resetPowerDownPin, HIGH); // Exit power down mode. This triggers a hard reset. digitalWrite(_resetPowerDownPin, HIGH); // Exit power down mode. This triggers a hard reset.
// Section 8.8.2 in the datasheet says the oscillator start-up time is the start up time of the crystal + 37,74μs. Let us be generous: 50ms. // Section 8.8.2 in the datasheet says the oscillator start-up time is the start up time of the crystal + 37,74μs. Let us be generous: 50ms.
delay(50); delay(50);