External SD Card
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@manju2391 said in External SD Card:
I'm using Catalex Micro SD Card adapter which uses SPI pins.
https://www.google.com.au/search?q=catalex+micro+sd+card+adapter+datasheet&rlz=1C1CHBF_en-GBAU760AU760&tbm=isch&source=iu&pf=m&ictx=1&fir=DHR2Q6L_pvc-M%253A%252CO21LzES_2VLsTM%252C&usg=__XDM0G6olWPNV09RPlFPnxzGgHyo%3D&sa=X&ved=0ahUKEwj3_puTi6HXAhXIFJQKHdpNASMQ9QEIOTAC#imgrc=SAdHIXZFJd1dvM: -
@manju2391
As we talking privately you do not need this module at all
only direct connection of SD card or simple adapter (without any electronic elements).But if you really need to use some SPI based module (I will see need for this only when you need more then one SD card) then try this
https://github.com/pycom/pycom-micropython-sigfox/tree/master/drivers/sdcard -
@livius
Sorry for the late reply was out of town. I still couldn't figure out how spi works on pycom chip. I'm just confused about the pins . -
I got it working with SDIO bus but is it possible over shared SPI bus?
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@manju2391
If you look below you find linkBut if you really need to use some SPI based module (I will see need for this only when you need more then one SD card) then try this
https://github.com/pycom/pycom-micropython-sigfox/tree/master/drivers/sdcardbut i haven't used it and cannot say more about it.
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This post is deleted! -
@livius
Yes I did import the library and when tried to test it but i'm getting this errorimport machine, sdcard, os
from machine import SPI
from machine import Pinspi = SPI(0, mode=SPI.MASTER, baudrate=2000000, polarity=0, phase=0, pins=('P19','P20','P21'))
CS = Pin('P10', mode=Pin.OUT, pull=Pin.PULL_UP)
sd = sdcard.SDCard(machine.SPI(0), machine.Pin('P22'))Traceback (most recent call last):
File "<stdin>", line 9, in <module>
File "/flash/lib/sdcard.py", line 54, in init
File "/flash/lib/sdcard.py", line 79, in init_card
File "/flash/lib/sdcard.py", line 133, in cmd
AttributeError: 'Pin' object has no attribute 'low'MicroPython v1.8.6-839-g536c958c on 2017-11-15; LoPy with ESP32
Type "help()" for more information. -
@manju2391
you must addapt it to pycom sources
insteadlow()writevalue(0) -
@livius And value(1) instead of high().
That was a confusing change in the API, which broke a lot of code. -
@robert-hh @livius
I did change the values according to pycom sources but still its not liking it. I'm getting this error
File "/flash/sd.py", line 9
File "/flash/lib/sdcard.py", line 54, in_init_
File "/flash/lib/sdcard.py", line 79, in init_card
File "/flash/lib/sdcard.py", line 147, in cmd
Typeerror: extra positional arguments given -
@manju2391 It seems that this library is a little bit outdated. I know that I used this on an esp8266, and it worked. And the version on the micropython.org site seems to be a little bit more recent. (https://github.com/micropython/micropython/tree/master/drivers/sdcard). I can check, but not before the evening, which is in about 8 hours.
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@robert-hh
Is there any possibility to interface the SD card over shared SPI bus without using any
libraries? I have been getting my head around the SPI module from last week and I haven't got it yet. Not a problem @robert-hh you can let me know how it goes after testing -
@manju2391 I tried that driver, and I got it to the point where it showed some activity. The code is below. The sdcard SPI is connected to:
P9 (SS), P10(Clk), P11(MOSI) and P12 (MISO). It is started with:import sdcard, machine, os sd = sdcard.SDCard(machine.SPI(0), machine.Pin("P9")) os.mount(sd, "/card")But it is very unstable, runs at low speed only, and data read from the card contains the byte sequence "\x7f\x04" here and there. And sometimes lopy simply crashed. So it's nothing really usable at the moment.
I tried that with two different SD card adapters. One with embedded bus drivers, which is like the one you have, and one which is simply wiring. The latter runs well when connected to the genuine SD card pins of the xxPy, using the built-in SD card module.""" MicroPython driver for SD cards using SPI bus. Requires an SPI bus and a CS pin. Provides readblocks and writeblocks methods so the device can be mounted as a filesystem. Example usage on xxPy: import machine, sdcard, os sd = sdcard.SDCard(machine.SPI(0), machine.Pin("P9")) os.mount(sd, '/sd2') os.listdir('/sd2') """ from micropython import const import time _CMD_TIMEOUT = const(100) _R1_IDLE_STATE = const(1 << 0) #R1_ERASE_RESET = const(1 << 1) _R1_ILLEGAL_COMMAND = const(1 << 2) #R1_COM_CRC_ERROR = const(1 << 3) #R1_ERASE_SEQUENCE_ERROR = const(1 << 4) #R1_ADDRESS_ERROR = const(1 << 5) #R1_PARAMETER_ERROR = const(1 << 6) _TOKEN_CMD25 = const(0xfc) _TOKEN_STOP_TRAN = const(0xfd) _TOKEN_DATA = const(0xfe) class SDCard: def __init__(self, spi, cs): self.spi = spi self.cs = cs self.cmdbuf = bytearray(6) self.dummybuf = bytearray(512) for i in range(512): self.dummybuf[i] = 0xff self.dummybuf_memoryview = memoryview(self.dummybuf) # initialise the card self.init_card() def init_spi(self, baudrate): master = self.spi.MASTER self.spi.init(master, baudrate=baudrate, phase=0, polarity=0) def init_card(self): # init CS pin self.cs.init(self.cs.OUT, value=1) # init SPI bus; use low data rate for initialisation self.init_spi(100000) # clock card at least 100 cycles with cs high for i in range(16): self.spi.write(b'\xff') # CMD0: init card; should return _R1_IDLE_STATE (allow 5 attempts) for _ in range(5): if self.cmd(0, 0, 0x95) == _R1_IDLE_STATE: break else: raise OSError("no SD card") # CMD8: determine card version r = self.cmd(8, 0x01aa, 0x87, 4) if r == _R1_IDLE_STATE: self.init_card_v2() elif r == (_R1_IDLE_STATE | _R1_ILLEGAL_COMMAND): self.init_card_v1() else: raise OSError("couldn't determine SD card version") # get the number of sectors # CMD9: response R2 (R1 byte + 16-byte block read) if self.cmd(9, 0, 0, 0, False) != 0: raise OSError("no response from SD card") csd = bytearray(16) self.readinto(csd) if csd[0] & 0xc0 != 0x40: raise OSError("SD card CSD format not supported") self.sectors = ((csd[8] << 8 | csd[9]) + 1) * 2014 #print('sectors', self.sectors) # CMD16: set block length to 512 bytes if self.cmd(16, 512, 0) != 0: raise OSError("can't set 512 block size") # set to high data rate now that it's initialised #self.init_spi(100000) #self.init_spi(40000000) def init_card_v1(self): for i in range(_CMD_TIMEOUT): self.cmd(55, 0, 0) if self.cmd(41, 0, 0) == 0: self.cdv = 512 #print("[SDCard] v1 card") return raise OSError("timeout waiting for v1 card") def init_card_v2(self): for i in range(_CMD_TIMEOUT): time.sleep_ms(50) self.cmd(58, 0, 0, 4) self.cmd(55, 0, 0) if self.cmd(41, 0x40000000, 0) == 0: self.cmd(58, 0, 0, 4) self.cdv = 1 #print("[SDCard] v2 card") return raise OSError("timeout waiting for v2 card") def cmd(self, cmd, arg, crc, final=0, release=True): self.cs(0) # create and send the command buf = self.cmdbuf buf[0] = 0x40 | cmd buf[1] = arg >> 24 buf[2] = arg >> 16 buf[3] = arg >> 8 buf[4] = arg buf[5] = crc self.spi.write(buf) # wait for the response (response[7] == 0) for i in range(_CMD_TIMEOUT): response = self.spi.read(1, write=0xff)[0] if not (response & 0x80): # this could be a big-endian integer that we are getting here for j in range(final): self.spi.write(b'\xff') if release: self.cs(1) self.spi.write(b'\xff') return response # timeout self.cs(1) self.spi.write(b'\xff') return -1 def cmd_nodata(self, cmd): self.spi.write(cmd) self.spi.read(1, write=0xff) # ignore stuff byte for _ in range(_CMD_TIMEOUT): if self.spi.read(1, write=0xff)[0] == 0xff: self.cs(1) self.spi.write(b'\xff') return 0 # OK self.cs(1) self.spi.write(b'\xff') return 1 # timeout def readinto(self, buf): self.cs(0) # read until start byte (0xff) while self.spi.read(1, write=0xff)[0] != 0xfe: pass # read data mv = self.dummybuf_memoryview[:len(buf)] self.spi.write_readinto(mv, buf) # read checksum self.spi.write(b'\xff') self.spi.write(b'\xff') self.cs(1) self.spi.write(b'\xff') def write(self, token, buf): self.cs(0) # send: start of block, data, checksum self.spi.read(1, token) self.spi.write(buf) self.spi.write(b'\xff') self.spi.write(b'\xff') # check the response if (self.spi.read(1, 0xff)[0] & 0x1f) != 0x05: self.cs(1) self.spi.write(b'\xff') return # wait for write to finish while self.spi.read(1, 0xff)[0] == 0: pass self.cs(1) self.spi.write(b'\xff') def write_token(self, token): self.cs(0) self.spi.read(1, token) self.spi.write(b'\xff') # wait for write to finish while self.spi.read(1, 0xff)[0] == 0x00: pass self.cs(1) self.spi.write(b'\xff') def count(self): return self.sectors def readblocks(self, block_num, buf): nblocks, err = divmod(len(buf), 512) assert nblocks and not err, 'Buffer length is invalid' if nblocks == 1: # CMD17: set read address for single block if self.cmd(17, block_num * self.cdv, 0) != 0: return 1 # receive the data self.readinto(buf) else: # CMD18: set read address for multiple blocks if self.cmd(18, block_num * self.cdv, 0) != 0: return 1 offset = 0 mv = memoryview(buf) while nblocks: self.readinto(mv[offset : offset + 512]) offset += 512 nblocks -= 1 return self.cmd_nodata(b'\x0c') # cmd 12 return 0 def writeblocks(self, block_num, buf): nblocks, err = divmod(len(buf), 512) assert nblocks and not err, 'Buffer length is invalid' if nblocks == 1: # CMD24: set write address for single block if self.cmd(24, block_num * self.cdv, 0) != 0: return 1 # send the data self.write(_TOKEN_DATA, buf) else: # CMD25: set write address for first block if self.cmd(25, block_num * self.cdv, 0) != 0: return 1 # send the data offset = 0 mv = memoryview(buf) while nblocks: self.write(_TOKEN_CMD25, mv[offset : offset + 512]) offset += 512 nblocks -= 1 self.write_token(_TOKEN_STOP_TRAN) return 0 -
@robert-hh
Thanks for your reply robert and I'll try working on it today and will post if anything crashes up and I have one more doubt regarding the WLAN access point. I have created an access point and I want to connect to my AP whenever the boot.py loads up. I can connect as a station but not as an access point i tried using this syntax but whenever it boots up it's looking for wlan AP but couldn't find it and goes to deep sleep mode. My network is up and it runs when I run it externally but not during boot up.from network import WLAN
wlan.init(mode=WLAN.STA_AP,ssid='AP')
wlan.init(ssid='AP',auth=(WLAN.WPA2,'xxxx'))
print(wlan.ifconfig())Is the above syntax right?
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@manju2391 About WLAN: It could look like:
from network import WLAN wlan = WLAN(mode=WLAN.STA_AP) wlan.connect(ssid='AP',auth=(WLAN.WPA2, 'xxxx')) # from here on it's optional. It just takes a few moments to connect for _ in range (200): if wlan.isconnected(): print(wlan.ifconfig()) break else: time.sleep_ms(50) else: print("Could not connect") -
I tried using SPI bus it is very slow. I had designed the pcb with spi pins but looks like it is not best so I’m just using the SDIO pins and changed the pcb. About the WLAN when I define wlan initially it is asking me for ap ssid at first I get an error saying ap ssid not given. I get the IP address when run locally and it connects to FileZilla but when it boots for the STA_AP it doesn’t print the IP address nor it connects to WLAN. It will be in idle state. I don’t know why it’s not connecting. I’m wondering should we create a station first and then an AP?
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@robert-hh said in External SD Card:
""" MicroPython driver for SD cards using SPI bus. Requires an SPI bus and a CS pin. Provides readblocks and writeblocks methods so the device can be mounted as a filesystem. Example usage on xxPy: import machine, sdcard, os sd = sdcard.SDCard(machine.SPI(0), machine.Pin("P9")) os.mount(sd, '/sd2') os.listdir('/sd2') """ from micropython import const import time _CMD_TIMEOUT = const(100) _R1_IDLE_STATE = const(1 << 0) #R1_ERASE_RESET = const(1 << 1) _R1_ILLEGAL_COMMAND = const(1 << 2) #R1_COM_CRC_ERROR = const(1 << 3) #R1_ERASE_SEQUENCE_ERROR = const(1 << 4) #R1_ADDRESS_ERROR = const(1 << 5) #R1_PARAMETER_ERROR = const(1 << 6) _TOKEN_CMD25 = const(0xfc) _TOKEN_STOP_TRAN = const(0xfd) _TOKEN_DATA = const(0xfe) class SDCard: def __init__(self, spi, cs): self.spi = spi self.cs = cs self.cmdbuf = bytearray(6) self.dummybuf = bytearray(512) for i in range(512): self.dummybuf[i] = 0xff self.dummybuf_memoryview = memoryview(self.dummybuf) # initialise the card self.init_card() def init_spi(self, baudrate): master = self.spi.MASTER self.spi.init(master, baudrate=baudrate, phase=0, polarity=0) def init_card(self): # init CS pin self.cs.init(self.cs.OUT, value=1) # init SPI bus; use low data rate for initialisation self.init_spi(100000) # clock card at least 100 cycles with cs high for i in range(16): self.spi.write(b'\xff') # CMD0: init card; should return _R1_IDLE_STATE (allow 5 attempts) for _ in range(5): if self.cmd(0, 0, 0x95) == _R1_IDLE_STATE: break else: raise OSError("no SD card") # CMD8: determine card version r = self.cmd(8, 0x01aa, 0x87, 4) if r == _R1_IDLE_STATE: self.init_card_v2() elif r == (_R1_IDLE_STATE | _R1_ILLEGAL_COMMAND): self.init_card_v1() else: raise OSError("couldn't determine SD card version") # get the number of sectors # CMD9: response R2 (R1 byte + 16-byte block read) if self.cmd(9, 0, 0, 0, False) != 0: raise OSError("no response from SD card") csd = bytearray(16) self.readinto(csd) if csd[0] & 0xc0 != 0x40: raise OSError("SD card CSD format not supported") self.sectors = ((csd[8] << 8 | csd[9]) + 1) * 2014 #print('sectors', self.sectors) # CMD16: set block length to 512 bytes if self.cmd(16, 512, 0) != 0: raise OSError("can't set 512 block size") # set to high data rate now that it's initialised #self.init_spi(100000) #self.init_spi(40000000) def init_card_v1(self): for i in range(_CMD_TIMEOUT): self.cmd(55, 0, 0) if self.cmd(41, 0, 0) == 0: self.cdv = 512 #print("[SDCard] v1 card") return raise OSError("timeout waiting for v1 card") def init_card_v2(self): for i in range(_CMD_TIMEOUT): time.sleep_ms(50) self.cmd(58, 0, 0, 4) self.cmd(55, 0, 0) if self.cmd(41, 0x40000000, 0) == 0: self.cmd(58, 0, 0, 4) self.cdv = 1 #print("[SDCard] v2 card") return raise OSError("timeout waiting for v2 card") def cmd(self, cmd, arg, crc, final=0, release=True): self.cs(0) # create and send the command buf = self.cmdbuf buf[0] = 0x40 | cmd buf[1] = arg >> 24 buf[2] = arg >> 16 buf[3] = arg >> 8 buf[4] = arg buf[5] = crc self.spi.write(buf) # wait for the response (response[7] == 0) for i in range(_CMD_TIMEOUT): response = self.spi.read(1, write=0xff)[0] if not (response & 0x80): # this could be a big-endian integer that we are getting here for j in range(final): self.spi.write(b'\xff') if release: self.cs(1) self.spi.write(b'\xff') return response # timeout self.cs(1) self.spi.write(b'\xff') return -1 def cmd_nodata(self, cmd): self.spi.write(cmd) self.spi.read(1, write=0xff) # ignore stuff byte for _ in range(_CMD_TIMEOUT): if self.spi.read(1, write=0xff)[0] == 0xff: self.cs(1) self.spi.write(b'\xff') return 0 # OK self.cs(1) self.spi.write(b'\xff') return 1 # timeout def readinto(self, buf): self.cs(0) # read until start byte (0xff) while self.spi.read(1, write=0xff)[0] != 0xfe: pass # read data mv = self.dummybuf_memoryview[:len(buf)] self.spi.write_readinto(mv, buf) # read checksum self.spi.write(b'\xff') self.spi.write(b'\xff') self.cs(1) self.spi.write(b'\xff') def write(self, token, buf): self.cs(0) # send: start of block, data, checksum self.spi.read(1, token) self.spi.write(buf) self.spi.write(b'\xff') self.spi.write(b'\xff') # check the response if (self.spi.read(1, 0xff)[0] & 0x1f) != 0x05: self.cs(1) self.spi.write(b'\xff') return # wait for write to finish while self.spi.read(1, 0xff)[0] == 0: pass self.cs(1) self.spi.write(b'\xff') def write_token(self, token): self.cs(0) self.spi.read(1, token) self.spi.write(b'\xff') # wait for write to finish while self.spi.read(1, 0xff)[0] == 0x00: pass self.cs(1) self.spi.write(b'\xff') def count(self): return self.sectors def readblocks(self, block_num, buf): nblocks, err = divmod(len(buf), 512) assert nblocks and not err, 'Buffer length is invalid' if nblocks == 1: # CMD17: set read address for single block if self.cmd(17, block_num * self.cdv, 0) != 0: return 1 # receive the data self.readinto(buf) else: # CMD18: set read address for multiple blocks if self.cmd(18, block_num * self.cdv, 0) != 0: return 1 offset = 0 mv = memoryview(buf) while nblocks: self.readinto(mv[offset : offset + 512]) offset += 512 nblocks -= 1 return self.cmd_nodata(b'\x0c') # cmd 12 return 0 def writeblocks(self, block_num, buf): nblocks, err = divmod(len(buf), 512) assert nblocks and not err, 'Buffer length is invalid' if nblocks == 1: # CMD24: set write address for single block if self.cmd(24, block_num * self.cdv, 0) != 0: return 1 # send the data self.write(_TOKEN_DATA, buf) else: # CMD25: set write address for first block if self.cmd(25, block_num * self.cdv, 0) != 0: return 1 # send the data offset = 0 mv = memoryview(buf) while nblocks: self.write(_TOKEN_CMD25, mv[offset : offset + 512]) offset += 512 nblocks -= 1 self.write_token(_TOKEN_STOP_TRAN) return 0I know this is a bit old but I just got an SD card module (https://www.sparkfun.com/products/13743) and was trying to get it working with my FiPy. I was running into a lot of issues but was able to make some headway using the library you pasted @robert-hh and thought I would share my results in case other people wanted to get it working.
However, I did have some errors with the library and had to make the following changes:
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The pins you used are not the default pins for the SPI init call. So I created my own SPI instance with the pin allocation you had in the post (since I already had them like that) and passed that instance into the SDCard constructor rather than
machine.SPI(0). I also removed the additional spi init calls. -
I had to set the SPI baudrate to 1000000 instead of 100000
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I had to declare the CS pin as an instance outside of the library and pass it in similar to the SPI above.
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The command to check idle state at the start of the library
self.cmd(0, 0, 0x95)would never return a value of 1. I don't know where the reference of these commands were but testing the other commands manually all returned values as expected.So I commented out the entire block that checks for the SD card or raises the 'no SD card' error.I found that I still need to run this command regardless, I get the same set of (4?) different values that repeat each time it is called. They never equal 1 but I let the code continue and command out the error block. Not calling the0x95command will not allow the next set of command to work correctly.
Doing the above I have gotten my external SD card board working fine with the FiPy. For reference below are my library and how I call it.
""" MicroPython driver for SD cards using SPI bus. Requires an SPI bus and a CS pin. Provides readblocks and writeblocks methods so the device can be mounted as a filesystem. Example usage on xxPy: import machine, sdcard, os sd = sdcard.SDCard(machine.SPI(0), machine.Pin("P9")) os.mount(sd, '/sd2') os.listdir('/sd2') """ from micropython import const import time _CMD_TIMEOUT = const(100) _R1_IDLE_STATE = const(1 << 0) #R1_ERASE_RESET = const(1 << 1) _R1_ILLEGAL_COMMAND = const(1 << 2) #R1_COM_CRC_ERROR = const(1 << 3) #R1_ERASE_SEQUENCE_ERROR = const(1 << 4) #R1_ADDRESS_ERROR = const(1 << 5) #R1_PARAMETER_ERROR = const(1 << 6) _TOKEN_CMD25 = const(0xfc) _TOKEN_STOP_TRAN = const(0xfd) _TOKEN_DATA = const(0xfe) class SDCard: def __init__(self, spi, cs): self.spi = spi self.cs = cs self.cmdbuf = bytearray(6) self.dummybuf = bytearray(512) for i in range(512): self.dummybuf[i] = 0xff self.dummybuf_memoryview = memoryview(self.dummybuf) # initialise the card self.init_card() def init_spi(self, baudrate): master = self.spi.MASTER self.spi.init(master, baudrate=baudrate, phase=0, polarity=0) def init_card(self): # init CS pin #self.cs.init(self.cs.OUT, value=0) # init SPI bus; use low data rate for initialisation #self.init_spi(100000) # clock card at least 100 cycles with cs high for i in range(16): self.spi.write(b'\xff') # CMD0: init card; should return _R1_IDLE_STATE (allow 5 attempts) for _ in range(5): if self.cmd(0, 0, 0x95) == _R1_IDLE_STATE: break ''' else: raise OSError("no SD card") ''' # CMD8: determine card version r = self.cmd(8, 0x01aa, 0x87, 4) if r == _R1_IDLE_STATE: self.init_card_v2() elif r == (_R1_IDLE_STATE | _R1_ILLEGAL_COMMAND): self.init_card_v1() else: raise OSError("couldn't determine SD card version") # get the number of sectors # CMD9: response R2 (R1 byte + 16-byte block read) if self.cmd(9, 0, 0, 0, False) != 0: raise OSError("no response from SD card") csd = bytearray(16) self.readinto(csd) if csd[0] & 0xc0 != 0x40: raise OSError("SD card CSD format not supported") self.sectors = ((csd[8] << 8 | csd[9]) + 1) * 2014 #print('sectors', self.sectors) # CMD16: set block length to 512 bytes if self.cmd(16, 512, 0) != 0: raise OSError("can't set 512 block size") # set to high data rate now that it's initialised #self.init_spi(100000) #self.init_spi(40000000) def init_card_v1(self): for i in range(_CMD_TIMEOUT): self.cmd(55, 0, 0) if self.cmd(41, 0, 0) == 0: self.cdv = 512 #print("[SDCard] v1 card") return raise OSError("timeout waiting for v1 card") def init_card_v2(self): for i in range(_CMD_TIMEOUT): time.sleep_ms(50) self.cmd(58, 0, 0, 4) self.cmd(55, 0, 0) if self.cmd(41, 0x40000000, 0) == 0: self.cmd(58, 0, 0, 4) self.cdv = 1 #print("[SDCard] v2 card") return raise OSError("timeout waiting for v2 card") def cmd(self, cmd, arg, crc, final=0, release=True): self.cs(0) # create and send the command buf = self.cmdbuf buf[0] = 0x40 | cmd buf[1] = arg >> 24 buf[2] = arg >> 16 buf[3] = arg >> 8 buf[4] = arg buf[5] = crc self.spi.write(buf) # wait for the response (response[7] == 0) for i in range(_CMD_TIMEOUT): response = self.spi.read(1, write=0xff)[0] if not (response & 0x80): # this could be a big-endian integer that we are getting here for j in range(final): self.spi.write(b'\xff') if release: self.cs(1) self.spi.write(b'\xff') return response # timeout self.cs(1) self.spi.write(b'\xff') return -1 def cmd_nodata(self, cmd): self.spi.write(cmd) self.spi.read(1, write=0xff) # ignore stuff byte for _ in range(_CMD_TIMEOUT): if self.spi.read(1, write=0xff)[0] == 0xff: self.cs(1) self.spi.write(b'\xff') return 0 # OK self.cs(1) self.spi.write(b'\xff') return 1 # timeout def readinto(self, buf): self.cs(0) # read until start byte (0xff) while self.spi.read(1, write=0xff)[0] != 0xfe: pass # read data mv = self.dummybuf_memoryview[:len(buf)] self.spi.write_readinto(mv, buf) # read checksum self.spi.write(b'\xff') self.spi.write(b'\xff') self.cs(1) self.spi.write(b'\xff') def write(self, token, buf): self.cs(0) # send: start of block, data, checksum self.spi.read(1, token) self.spi.write(buf) self.spi.write(b'\xff') self.spi.write(b'\xff') # check the response if (self.spi.read(1, 0xff)[0] & 0x1f) != 0x05: self.cs(1) self.spi.write(b'\xff') return # wait for write to finish while self.spi.read(1, 0xff)[0] == 0: pass self.cs(1) self.spi.write(b'\xff') def write_token(self, token): self.cs(0) self.spi.read(1, token) self.spi.write(b'\xff') # wait for write to finish while self.spi.read(1, 0xff)[0] == 0x00: pass self.cs(1) self.spi.write(b'\xff') def count(self): return self.sectors def readblocks(self, block_num, buf): nblocks, err = divmod(len(buf), 512) assert nblocks and not err, 'Buffer length is invalid' if nblocks == 1: # CMD17: set read address for single block if self.cmd(17, block_num * self.cdv, 0) != 0: return 1 # receive the data self.readinto(buf) else: # CMD18: set read address for multiple blocks if self.cmd(18, block_num * self.cdv, 0) != 0: return 1 offset = 0 mv = memoryview(buf) while nblocks: self.readinto(mv[offset : offset + 512]) offset += 512 nblocks -= 1 return self.cmd_nodata(b'\x0c') # cmd 12 return 0 def writeblocks(self, block_num, buf): nblocks, err = divmod(len(buf), 512) assert nblocks and not err, 'Buffer length is invalid' if nblocks == 1: # CMD24: set write address for single block if self.cmd(24, block_num * self.cdv, 0) != 0: return 1 # send the data self.write(_TOKEN_DATA, buf) else: # CMD25: set write address for first block if self.cmd(25, block_num * self.cdv, 0) != 0: return 1 # send the data offset = 0 mv = memoryview(buf) while nblocks: self.write(_TOKEN_CMD25, mv[offset : offset + 512]) offset += 512 nblocks -= 1 self.write_token(_TOKEN_STOP_TRAN) return 0from machine import SPI from machine import Pin import machine, sdcard, os spi = SPI(0, mode=SPI.MASTER, baudrate=1000000, polarity=0, phase=0, pins=('P10','P11','P12')) cs = Pin('P9', Pin.OUT) sd = sdcard.SDCard(spi, cs) os.mount(sd, "/card")I could probably tidy up the library to initialise the SPI and CS properly internally but this got me going at least.
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@jmarcelino Would this wiring work?
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@edward-dimmack That should work. I'm using this wiring on my homebrew interface boards.
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