I was following this tutorial, but it isn’t working since the python modules used only work Raspberry Pi.
I tried modifying the MFRC522 module so that it didn’t depend on RPi.GPIO, but that didn’t seem to work. The program starts up but nothing is ever read.
What other alternatives are there to get this working?
main file:
from module.mfrc522 import SimpleMFRC522
reader = SimpleMFRC522()
id, text = reader.read()
print(id)
print(text)
This is my modified MFRC522
SimpleMFRC522 is kept the same but I just removed the RPi.GPIO import.
Which board are you using? I have one of these kicking around, I can try it on my S905X.
It is a Le Potato, S905X.
Ok, I don’t have a lot of experience with SPI, but I’ll give it a try. I’m working a lot of overtime right now, so it might be a bit.
Thanks! Take your time.
Instead of the Raspberry Pi SPI instructions, you can enable SPI on Le Potato like this:
Then just run the Python script.
I think something still needs to replace that RPi.GPIO library to handle that one lonely reset pin. I have a rough idea how do do it, just need the time. If I’m not too exhausted after work, I’ll give it a crack tonight. 70 hr. weeks don’t leave a lot of time for tinkering.
Also, I had to download the whole module from github, since RPi.GPIO seems to be used in SimpleMFRC522.py too. That and I’d like to test it for myself. I’ve only used SPI to connect a microcontroller to an LCD, so I’m in uncharted waters.
RPi.GPIO is not a good library. Best to avoid using it in any application. To modify a GPIO, look up the GPIO chip number and line number and use those directly via libgpiod.
Thank you so much for your time! No worries about the speed, take your time.
Still doesn’t seem to work.
You are doing a step incorrectly if that is the case. lgpio tool directly uses libgpiod so it is definitely working.
Just managed to wrap my head around libgpiod. I’ll try to apply what I’ve learned tonight when I get home from work.
the only pin being modified directly is the rst, but I will send pictures tomorrow of my setup to ensure everything is right. thanks!
Still getting errors here or there, but works for the most part.
First, enable spi with sudo ldto enable spicc spicc-spidev
I put the following files in the same directory instead of installing as a module. I left most of the original code commented out so you can see what I changed, otherwise just the import statements got shuffled. I hope this is helpful, I definitely learned a lot in the process. Thanks to @librecomputer for all the guidance.
MFRC522.py:
#!/usr/bin/env python
# -*- coding: utf8 -*-
#
# Copyright 2014,2018 Mario Gomez <mario.gomez@teubi.co>
#
# This file is part of MFRC522-Python
# MFRC522-Python is a simple Python implementation for
# the MFRC522 NFC Card Reader for the Raspberry Pi.
#
# MFRC522-Python is free software: you can redistribute it and/or modify
# it under the terms of the GNU Lesser General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# MFRC522-Python is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public License
# along with MFRC522-Python. If not, see <http://www.gnu.org/licenses/>.
#
# Modified by Angus for use with Libre Computer AML-S905X-CC "le Potato"
# 1-April-2013
#import RPi.GPIO as GPIO
# Replaced RPi lib with libgpiod
import gpiod
import spidev
import signal
import time
import logging
class MFRC522:
MAX_LEN = 16
PCD_IDLE = 0x00
PCD_AUTHENT = 0x0E
PCD_RECEIVE = 0x08
PCD_TRANSMIT = 0x04
PCD_TRANSCEIVE = 0x0C
PCD_RESETPHASE = 0x0F
PCD_CALCCRC = 0x03
PICC_REQIDL = 0x26
PICC_REQALL = 0x52
PICC_ANTICOLL = 0x93
PICC_SElECTTAG = 0x93
PICC_AUTHENT1A = 0x60
PICC_AUTHENT1B = 0x61
PICC_READ = 0x30
PICC_WRITE = 0xA0
PICC_DECREMENT = 0xC0
PICC_INCREMENT = 0xC1
PICC_RESTORE = 0xC2
PICC_TRANSFER = 0xB0
PICC_HALT = 0x50
MI_OK = 0
MI_NOTAGERR = 1
MI_ERR = 2
Reserved00 = 0x00
CommandReg = 0x01
CommIEnReg = 0x02
DivlEnReg = 0x03
CommIrqReg = 0x04
DivIrqReg = 0x05
ErrorReg = 0x06
Status1Reg = 0x07
Status2Reg = 0x08
FIFODataReg = 0x09
FIFOLevelReg = 0x0A
WaterLevelReg = 0x0B
ControlReg = 0x0C
BitFramingReg = 0x0D
CollReg = 0x0E
Reserved01 = 0x0F
Reserved10 = 0x10
ModeReg = 0x11
TxModeReg = 0x12
RxModeReg = 0x13
TxControlReg = 0x14
TxAutoReg = 0x15
TxSelReg = 0x16
RxSelReg = 0x17
RxThresholdReg = 0x18
DemodReg = 0x19
Reserved11 = 0x1A
Reserved12 = 0x1B
MifareReg = 0x1C
Reserved13 = 0x1D
Reserved14 = 0x1E
SerialSpeedReg = 0x1F
Reserved20 = 0x20
CRCResultRegM = 0x21
CRCResultRegL = 0x22
Reserved21 = 0x23
ModWidthReg = 0x24
Reserved22 = 0x25
RFCfgReg = 0x26
GsNReg = 0x27
CWGsPReg = 0x28
ModGsPReg = 0x29
TModeReg = 0x2A
TPrescalerReg = 0x2B
TReloadRegH = 0x2C
TReloadRegL = 0x2D
TCounterValueRegH = 0x2E
TCounterValueRegL = 0x2F
Reserved30 = 0x30
TestSel1Reg = 0x31
TestSel2Reg = 0x32
TestPinEnReg = 0x33
TestPinValueReg = 0x34
TestBusReg = 0x35
AutoTestReg = 0x36
VersionReg = 0x37
AnalogTestReg = 0x38
TestDAC1Reg = 0x39
TestDAC2Reg = 0x3A
TestADCReg = 0x3B
Reserved31 = 0x3C
Reserved32 = 0x3D
Reserved33 = 0x3E
Reserved34 = 0x3F
serNum = []
def __init__(self, bus=0, device=0, spd=1000000, debugLevel='WARNING'): # removed " pin_mode=10, pin_rst=-1," from args
self.spi = spidev.SpiDev()
self.spi.open(bus, device)
self.spi.max_speed_hz = spd
self.logger = logging.getLogger('mfrc522Logger')
self.logger.addHandler(logging.StreamHandler())
level = logging.getLevelName(debugLevel)
self.logger.setLevel(level)
# replaced RPi code with libgpiod, no option for pin 15 anymore
# gpioMode = GPIO.getmode()
# if gpioMode is None:
# GPIO.setmode(pin_mode)
# else:
# pin_mode = gpioMode
# if pin_rst == -1:
# if pin_mode == 11:
# pin_rst = 15
# else:
# pin_rst = 22
# GPIO.setup(pin_rst, GPIO.OUT)
# GPIO.output(pin_rst, 1)
chip = gpiod.Chip('1') # set the chip number
lines = chip.get_lines([79]) # setthe line number
lines.request(consumer='spam', type=gpiod.LINE_REQ_DIR_OUT, default_vals=[1]) # set direction and value
self.MFRC522_Init()
def MFRC522_Reset(self):
self.Write_MFRC522(self.CommandReg, self.PCD_RESETPHASE)
def Write_MFRC522(self, addr, val):
val = self.spi.xfer2([(addr << 1) & 0x7E, val])
def Read_MFRC522(self, addr):
val = self.spi.xfer2([((addr << 1) & 0x7E) | 0x80, 0])
return val[1]
def Close_MFRC522(self):
self.spi.close()
lines.set_values([0])
#GPIO.cleanup()
def SetBitMask(self, reg, mask):
tmp = self.Read_MFRC522(reg)
self.Write_MFRC522(reg, tmp | mask)
def ClearBitMask(self, reg, mask):
tmp = self.Read_MFRC522(reg)
self.Write_MFRC522(reg, tmp & (~mask))
def AntennaOn(self):
temp = self.Read_MFRC522(self.TxControlReg)
if (~(temp & 0x03)):
self.SetBitMask(self.TxControlReg, 0x03)
def AntennaOff(self):
self.ClearBitMask(self.TxControlReg, 0x03)
def MFRC522_ToCard(self, command, sendData):
backData = []
backLen = 0
status = self.MI_ERR
irqEn = 0x00
waitIRq = 0x00
lastBits = None
n = 0
if command == self.PCD_AUTHENT:
irqEn = 0x12
waitIRq = 0x10
if command == self.PCD_TRANSCEIVE:
irqEn = 0x77
waitIRq = 0x30
self.Write_MFRC522(self.CommIEnReg, irqEn | 0x80)
self.ClearBitMask(self.CommIrqReg, 0x80)
self.SetBitMask(self.FIFOLevelReg, 0x80)
self.Write_MFRC522(self.CommandReg, self.PCD_IDLE)
for i in range(len(sendData)):
self.Write_MFRC522(self.FIFODataReg, sendData[i])
self.Write_MFRC522(self.CommandReg, command)
if command == self.PCD_TRANSCEIVE:
self.SetBitMask(self.BitFramingReg, 0x80)
i = 2000
while True:
n = self.Read_MFRC522(self.CommIrqReg)
i -= 1
if ~((i != 0) and ~(n & 0x01) and ~(n & waitIRq)):
break
self.ClearBitMask(self.BitFramingReg, 0x80)
if i != 0:
if (self.Read_MFRC522(self.ErrorReg) & 0x1B) == 0x00:
status = self.MI_OK
if n & irqEn & 0x01:
status = self.MI_NOTAGERR
if command == self.PCD_TRANSCEIVE:
n = self.Read_MFRC522(self.FIFOLevelReg)
lastBits = self.Read_MFRC522(self.ControlReg) & 0x07
if lastBits != 0:
backLen = (n - 1) * 8 + lastBits
else:
backLen = n * 8
if n == 0:
n = 1
if n > self.MAX_LEN:
n = self.MAX_LEN
for i in range(n):
backData.append(self.Read_MFRC522(self.FIFODataReg))
else:
status = self.MI_ERR
return (status, backData, backLen)
def MFRC522_Request(self, reqMode):
status = None
backBits = None
TagType = []
self.Write_MFRC522(self.BitFramingReg, 0x07)
TagType.append(reqMode)
(status, backData, backBits) = self.MFRC522_ToCard(self.PCD_TRANSCEIVE, TagType)
if ((status != self.MI_OK) | (backBits != 0x10)):
status = self.MI_ERR
return (status, backBits)
def MFRC522_Anticoll(self):
backData = []
serNumCheck = 0
serNum = []
self.Write_MFRC522(self.BitFramingReg, 0x00)
serNum.append(self.PICC_ANTICOLL)
serNum.append(0x20)
(status, backData, backBits) = self.MFRC522_ToCard(self.PCD_TRANSCEIVE, serNum)
if (status == self.MI_OK):
i = 0
if len(backData) == 5:
for i in range(4):
serNumCheck = serNumCheck ^ backData[i]
if serNumCheck != backData[4]:
status = self.MI_ERR
else:
status = self.MI_ERR
return (status, backData)
def CalulateCRC(self, pIndata):
self.ClearBitMask(self.DivIrqReg, 0x04)
self.SetBitMask(self.FIFOLevelReg, 0x80)
for i in range(len(pIndata)):
self.Write_MFRC522(self.FIFODataReg, pIndata[i])
self.Write_MFRC522(self.CommandReg, self.PCD_CALCCRC)
i = 0xFF
while True:
n = self.Read_MFRC522(self.DivIrqReg)
i -= 1
if not ((i != 0) and not (n & 0x04)):
break
pOutData = []
pOutData.append(self.Read_MFRC522(self.CRCResultRegL))
pOutData.append(self.Read_MFRC522(self.CRCResultRegM))
return pOutData
def MFRC522_SelectTag(self, serNum):
backData = []
buf = []
buf.append(self.PICC_SElECTTAG)
buf.append(0x70)
for i in range(5):
buf.append(serNum[i])
pOut = self.CalulateCRC(buf)
buf.append(pOut[0])
buf.append(pOut[1])
(status, backData, backLen) = self.MFRC522_ToCard(self.PCD_TRANSCEIVE, buf)
if (status == self.MI_OK) and (backLen == 0x18):
self.logger.debug("Size: " + str(backData[0]))
return backData[0]
else:
return 0
def MFRC522_Auth(self, authMode, BlockAddr, Sectorkey, serNum):
buff = []
# First byte should be the authMode (A or B)
buff.append(authMode)
# Second byte is the trailerBlock (usually 7)
buff.append(BlockAddr)
# Now we need to append the authKey which usually is 6 bytes of 0xFF
for i in range(len(Sectorkey)):
buff.append(Sectorkey[i])
# Next we append the first 4 bytes of the UID
for i in range(4):
buff.append(serNum[i])
# Now we start the authentication itself
(status, backData, backLen) = self.MFRC522_ToCard(self.PCD_AUTHENT, buff)
# Check if an error occurred
if not (status == self.MI_OK):
self.logger.error("AUTH ERROR!!")
if not (self.Read_MFRC522(self.Status2Reg) & 0x08) != 0:
self.logger.error("AUTH ERROR(status2reg & 0x08) != 0")
# Return the status
return status
def MFRC522_StopCrypto1(self):
self.ClearBitMask(self.Status2Reg, 0x08)
def MFRC522_Read(self, blockAddr):
recvData = []
recvData.append(self.PICC_READ)
recvData.append(blockAddr)
pOut = self.CalulateCRC(recvData)
recvData.append(pOut[0])
recvData.append(pOut[1])
(status, backData, backLen) = self.MFRC522_ToCard(self.PCD_TRANSCEIVE, recvData)
if not (status == self.MI_OK):
self.logger.error("Error while reading!")
if len(backData) == 16:
self.logger.debug("Sector " + str(blockAddr) + " " + str(backData))
return backData
else:
return None
def MFRC522_Write(self, blockAddr, writeData):
buff = []
buff.append(self.PICC_WRITE)
buff.append(blockAddr)
crc = self.CalulateCRC(buff)
buff.append(crc[0])
buff.append(crc[1])
(status, backData, backLen) = self.MFRC522_ToCard(self.PCD_TRANSCEIVE, buff)
if not (status == self.MI_OK) or not (backLen == 4) or not ((backData[0] & 0x0F) == 0x0A):
status = self.MI_ERR
self.logger.debug("%s backdata &0x0F == 0x0A %s" % (backLen, backData[0] & 0x0F))
if status == self.MI_OK:
buf = []
for i in range(16):
buf.append(writeData[i])
crc = self.CalulateCRC(buf)
buf.append(crc[0])
buf.append(crc[1])
(status, backData, backLen) = self.MFRC522_ToCard(self.PCD_TRANSCEIVE, buf)
if not (status == self.MI_OK) or not (backLen == 4) or not ((backData[0] & 0x0F) == 0x0A):
self.logger.error("Error while writing")
if status == self.MI_OK:
self.logger.debug("Data written")
def MFRC522_DumpClassic1K(self, key, uid):
for i in range(64):
status = self.MFRC522_Auth(self.PICC_AUTHENT1A, i, key, uid)
# Check if authenticated
if status == self.MI_OK:
self.MFRC522_Read(i)
else:
self.logger.error("Authentication error")
def MFRC522_Init(self):
self.MFRC522_Reset()
self.Write_MFRC522(self.TModeReg, 0x8D)
self.Write_MFRC522(self.TPrescalerReg, 0x3E)
self.Write_MFRC522(self.TReloadRegL, 30)
self.Write_MFRC522(self.TReloadRegH, 0)
self.Write_MFRC522(self.TxAutoReg, 0x40)
self.Write_MFRC522(self.ModeReg, 0x3D)
self.AntennaOn()
SimpleMFRC522.py:
# Code by Simon Monk https://github.com/simonmonk/
# Modified by Angus for use with Libre Computer AML-S905X-CC "le Potato"
# 1-April-2013
from MFRC522 import MFRC522
#import RPi.GPIO as GPIO
# Replaced fruity lib with libgpiod, though it does not seem to be used here.
import gpiod
class SimpleMFRC522:
READER = None
KEY = [0xFF,0xFF,0xFF,0xFF,0xFF,0xFF]
BLOCK_ADDRS = [8, 9, 10]
def __init__(self):
self.READER = MFRC522()
def read(self):
id, text = self.read_no_block()
while not id:
id, text = self.read_no_block()
return id, text
def read_id(self):
id = self.read_id_no_block()
while not id:
id = self.read_id_no_block()
return id
def read_id_no_block(self):
(status, TagType) = self.READER.MFRC522_Request(self.READER.PICC_REQIDL)
if status != self.READER.MI_OK:
return None
(status, uid) = self.READER.MFRC522_Anticoll()
if status != self.READER.MI_OK:
return None
return self.uid_to_num(uid)
def read_no_block(self):
(status, TagType) = self.READER.MFRC522_Request(self.READER.PICC_REQIDL)
if status != self.READER.MI_OK:
return None, None
(status, uid) = self.READER.MFRC522_Anticoll()
if status != self.READER.MI_OK:
return None, None
id = self.uid_to_num(uid)
self.READER.MFRC522_SelectTag(uid)
status = self.READER.MFRC522_Auth(self.READER.PICC_AUTHENT1A, 11, self.KEY, uid)
data = []
text_read = ''
if status == self.READER.MI_OK:
for block_num in self.BLOCK_ADDRS:
block = self.READER.MFRC522_Read(block_num)
if block:
data += block
if data:
text_read = ''.join(chr(i) for i in data)
self.READER.MFRC522_StopCrypto1()
return id, text_read
def write(self, text):
id, text_in = self.write_no_block(text)
while not id:
id, text_in = self.write_no_block(text)
return id, text_in
def write_no_block(self, text):
(status, TagType) = self.READER.MFRC522_Request(self.READER.PICC_REQIDL)
if status != self.READER.MI_OK:
return None, None
(status, uid) = self.READER.MFRC522_Anticoll()
if status != self.READER.MI_OK:
return None, None
id = self.uid_to_num(uid)
self.READER.MFRC522_SelectTag(uid)
status = self.READER.MFRC522_Auth(self.READER.PICC_AUTHENT1A, 11, self.KEY, uid)
self.READER.MFRC522_Read(11)
if status == self.READER.MI_OK:
data = bytearray()
data.extend(bytearray(text.ljust(len(self.BLOCK_ADDRS) * 16).encode('ascii')))
i = 0
for block_num in self.BLOCK_ADDRS:
self.READER.MFRC522_Write(block_num, data[(i*16):(i+1)*16])
i += 1
self.READER.MFRC522_StopCrypto1()
return id, text[0:(len(self.BLOCK_ADDRS) * 16)]
def uid_to_num(self, uid):
n = 0
for i in range(0, 5):
n = n * 256 + uid[i]
return n
write.py:
#!/usr/bin/env python
#import RPi.GPIO as GPIO
from SimpleMFRC522 import SimpleMFRC522
reader = SimpleMFRC522()
try:
text = input('New data:')
print("Now place your tag to write")
reader.write(text)
print("Written")
finally:
pass
#GPIO.cleanup()
read.py:
#!/usr/bin/env python
#import RPi.GPIO as GPIO
from SimpleMFRC522 import SimpleMFRC522
reader = SimpleMFRC522()
try:
id, text = reader.read()
print(id)
print(text)
finally:
pass
# GPIO.cleanup()
Sample Usage:
angus@aml-s905x-cc:~/Documents/MFRC522-python-master/mfrc522$ python3 write.py
New data:spam
Now place your tag to write
Written
angus@aml-s905x-cc:~/Documents/MFRC522-python-master/mfrc522$ python3 read.py
############
spam
I’ve been trying to set up the card reader with this code for a little bit but I’ve been having some issues for quite some time now. I attempted to use this code, I fixed a couple of capitalization issues and got the code to run but it’s not able to write to a card (Not able to detect when the blank RFID card is nearby). Looking into it I see that the line number is set to 79 (lines=chip.get_lines([79])
According to the setup guide we don’t use that pin? I’ve checked the connections as well and I’m positive I have the wires in the right place. My knowledge of hardware is pretty limited, so I’m assuming my issue is pretty simple. I’ve tried the other GPIO pins that we are connected to, thinking that maybe MISO or MOSI would work, but when I attempt to use their pins (19,21) i get the error that the device or resource is busy.
What pin should data be going in and out through exactly?
Any help would be really appreciated. I’m all open to learn more!
Edit:
Just learned that GPIO pin# != Line number after looking at ‘lgpio info’ data
I have now tried line 88, 87, 89, 90, and 79, but I’m still not getting anything.
Also just to mention I do 100% the reader works, I tested it on an arduino and it worked flawlessly. Unfortunately for the project I’d like to use it on, the arduino won’t cut it.
If it’s a SPI device, enable the SPI device and SPI userspace overlays and use /dev/spidev to send and receive data. Take the time to learn how to properly uses busses in Linux. Even better if there’s a kernel driver (ask the manufacturer) and just create an overlay for it.
You don’t bit bang GPIOs in software. RPi.GPIO is an unreliable piece of crap that should have never been made.
Would you be able to provide me more detail about what would go into SPI userspace overlays? If you had any good resources to learn more about it I would really appreciate it as well!