# Pico demo sd-card **URL:** \ **Category:** Support\ **Created:** [January 1, 2023, 11:03am UTC](https://forums.pimoroni.com/t/pico-demo-sd-card/21076 "2023-01-01T11:03:11Z")\ **Posts on this page:** 18\ **Page:** 1
**Author:** ![tonypigram](https://sea2.discourse-cdn.com/flex016/user_avatar/forums.pimoroni.com/tonypigram/32/9334_2.png) [@tonypigram](https://forums.pimoroni.com/u/tonypigram)\ **Post date:** [January 1, 2023, 11:03am UTC](https://forums.pimoroni.com/t/pico-demo-sd-card/21076/1 "2023-01-01T11:03:11Z")
Can anyone tell me what the correct values for using the sd-card on the pico demo board are? I have a FAT32 formatted sd-card, that has been tested and works in 2 other LCD screen sd-cards (using different GPIO values) and I can read/write and list the files/folders. Using the same code with the pico demo board, all I get now is ‘bad SCK pin’. I’m looking for something that maps: SD\_CLK : (GPIO 5) SD\_DAT3 : (GPIO 22) DAT2 : (GPIO 21) DAT1 : (GPIO 20) DAT0 : (GPIO 19) CMD : (GPIO 18) to the required values for CS, SCK, MOSI and MISO. The Hardware PDF does give me values - but they do not seem to work - did I mis-interpret them? [https://datasheets.raspberrypi.com/rp2040/hardware-design-with-rp2040.pdf](https://datasheets.raspberrypi.com/rp2040/hardware-design-with-rp2040.pdf) PAGE 21 This does not work as I expected it to in MicroPython code: cs = machine.Pin(18, machine.Pin.OUT, value=1) spi = machine.SPI(0, baudrate=1000000, polarity=0, phase=0, bits=8, firstbit=machine.SPI.MSB, sck=machine.Pin(5), mosi=machine.Pin(19), miso=machine.Pin(20)) sd = sdcard.SDCard(spi, cs) any assistance / guidance really appreciated! ---
**Author:** ![bablokb](https://avatars.discourse-cdn.com/v4/letter/b/ee59a6/32.png) [@bablokb](https://forums.pimoroni.com/u/bablokb)\ **Post date:** [January 2, 2023, 3:54pm UTC](https://forums.pimoroni.com/t/pico-demo-sd-card/21076/2 "2023-01-02T15:54:37Z")
‘bad SCK pin’ is the key to your problem: GPIO5 is not a valid SPI-SCK pin. See [https://pico.pinout.xyz/](https://pico.pinout.xyz/) ---
**Author:** ![tonypigram](https://sea2.discourse-cdn.com/flex016/user_avatar/forums.pimoroni.com/tonypigram/32/9334_2.png) [@tonypigram](https://forums.pimoroni.com/u/tonypigram)\ **Post date:** [January 2, 2023, 4:20pm UTC](https://forums.pimoroni.com/t/pico-demo-sd-card/21076/3 "2023-01-02T16:20:24Z")
Hi, yes, I did a bit more logical deduction last night using that layout and determined that it should be: CS = GPIO5 or GPIO22 - get same response SCK = GPIO18 (If I set the following two to any other value the MicroPython library quite nicely tells me I am wrong) MOSI = GPIO19 MISO =GPIO20 and now I get an error: OSError: no SD card I even set this up: [GitHub - carlk3/no-OS-FatFS-SD-SPI-RPi-Pico: A FAT filesystem with SPI driver for SD card on Raspberry Pi Pico](https://github.com/carlk3/no-OS-FatFS-SD-SPI-RPi-Pico) and built my own uf2 so I could test doing the “mount 0:” and debugging the errors from there. As I say, I can make this work repeatedly on other breadboard setups, just not on the pico demo and I cannot figure out why? I really don’t want to have wasted £20 on a pico demo just so I can have VGA - pretty pointless if I cannot get the sd-card working with it. There must be something “simple” I am missing here? ---
**Author:** ![bablokb](https://avatars.discourse-cdn.com/v4/letter/b/ee59a6/32.png) [@bablokb](https://forums.pimoroni.com/u/bablokb)\ **Post date:** [January 2, 2023, 5:59pm UTC](https://forums.pimoroni.com/t/pico-demo-sd-card/21076/4 "2023-01-02T17:59:30Z")
I checked the wiring and I’m sure now that the SD-card is wired not for the SPI interface, but the SDIO interface. I have no experience with that, until now I only used SPI (including carlk3’s implementation). I found this link [Pico w/4-bit SDIO interface example? - Raspberry Pi Forums](https://forums.raspberrypi.com/viewtopic.php?t=337143), but I’m not sure if this helps. ---
**Author:** ![tonypigram](https://sea2.discourse-cdn.com/flex016/user_avatar/forums.pimoroni.com/tonypigram/32/9334_2.png) [@tonypigram](https://forums.pimoroni.com/u/tonypigram)\ **Post date:** [January 4, 2023, 3:33pm UTC](https://forums.pimoroni.com/t/pico-demo-sd-card/21076/5 "2023-01-04T15:33:20Z")
Just a small update: I was doing some random digging & I can confirm that the actual values are: SCK: GPIO18 CS: GPIO22 MOSI: GPIO19 However, I still get the “SD Card not found” error… I was doing this as a “quick test” using MicroPython - just to make sure that I could read the sdcard from the device. I found the above values within some C/C++ code here: [https://github.com/fhoedemakers/pico-infonesPlus/blob/main/drivers/sdcard/sdcard.h](https://github.com/fhoedemakers/pico-infonesPlus/blob/main/drivers/sdcard/sdcard.h) …and that is when the realisation dawned on me…what if this doesn’t work from MicroPython! I then checked on the main product page…and, there it is at the top: **Please note that VGA Demo Base only currently works with the C/C++ Pico SDK!** Maybe it needs to be in a BIGGER font - I hang my head in shame… unfortunately, I still cannot get it to access the SDCard from C-code. Following the simple instructions from here: [Pico supports SD cards and FatFS - Hackster.io](https://www.hackster.io/kamaluddinkhan/pico-supports-sd-cards-and-fatfs-5b4fb5) I still get > mount 0: > sd\_spi\_go\_low\_frequency: Actual frequency: 398089 > sd\_wait\_ready failed > /home/tony/dev/pico/c-code/v2/no-OS-FatFS/FatFs\_SPI/sd\_driver/sd\_card.c:462: Card not ready yet > sd\_wait\_ready failed > /home/tony/dev/pico/c-code/v2/no-OS-FatFS/FatFs\_SPI/sd\_driver/sd\_card.c:462: Card not ready yet > sd\_wait\_ready failed I have tried several different sdcards, proven to work on other devices. am a bit stumped now. ---
**Author:** ![alphanumeric](https://sea2.discourse-cdn.com/flex016/user_avatar/forums.pimoroni.com/alphanumeric/32/2729_2.png) [@alphanumeric](https://forums.pimoroni.com/u/alphanumeric)\ **Post date:** [January 4, 2023, 8:14pm UTC](https://forums.pimoroni.com/t/pico-demo-sd-card/21076/6 "2023-01-04T20:14:02Z")
How are the SD Cards formatted? I think they need to be Fat formatted. ---
**Author:** ![tonypigram](https://sea2.discourse-cdn.com/flex016/user_avatar/forums.pimoroni.com/tonypigram/32/9334_2.png) [@tonypigram](https://forums.pimoroni.com/u/tonypigram)\ **Post date:** [January 4, 2023, 8:20pm UTC](https://forums.pimoroni.com/t/pico-demo-sd-card/21076/7 "2023-01-04T20:20:06Z")
yep, all FAT formatted. I have a 2Gb, 16GB and 32GB for variance ---
**Author:** ![alphanumeric](https://sea2.discourse-cdn.com/flex016/user_avatar/forums.pimoroni.com/alphanumeric/32/2729_2.png) [@alphanumeric](https://forums.pimoroni.com/u/alphanumeric)\ **Post date:** [January 4, 2023, 9:53pm UTC](https://forums.pimoroni.com/t/pico-demo-sd-card/21076/8 "2023-01-04T21:53:03Z")
Ok, was just a stab in the dark. ---
**Author:** ![tonypigram](https://sea2.discourse-cdn.com/flex016/user_avatar/forums.pimoroni.com/tonypigram/32/9334_2.png) [@tonypigram](https://forums.pimoroni.com/u/tonypigram)\ **Post date:** [January 4, 2023, 10:15pm UTC](https://forums.pimoroni.com/t/pico-demo-sd-card/21076/9 "2023-01-04T22:15:31Z")
no worries! I’ve been doing a lot of that recently with this. Am open to all / any suggestions. I’ve just hacked up some waveshare C code that accesses the sdcard on their 2.8" touchscreen - am basically removing all references to the LCD display… am nearly there. I have that code successfully accessing the sdcard on that device (_the previous mentioned code ‘no-OS-FatFS’ was failing to access this sdcard too_). However, I now have a list of files being output and I can navigate into sub-folders and list them too, so some success on the waveshield device! I’ll look to clean this code up and then see if I can move it over to then try it on the pico demo board… just have to change the config PINS… in theory… ---
**Author:** ![bablokb](https://avatars.discourse-cdn.com/v4/letter/b/ee59a6/32.png) [@bablokb](https://forums.pimoroni.com/u/bablokb)\ **Post date:** [January 5, 2023, 7:15am UTC](https://forums.pimoroni.com/t/pico-demo-sd-card/21076/10 "2023-01-05T07:15:00Z")
I still don’t think that you will be able to access the SD-card on the pico-demo with SPI. According to the pinout on the product page, SD-CLK is wired to pin7, i.e. GP5, which is not a SPI clock-pin on the pico. You are claiming that GPIO18 is SPI-SCK, but that pin is wired to SD-CMD (where you expect MOSI in SPI-mode). ---
**Author:** ![tonypigram](https://sea2.discourse-cdn.com/flex016/user_avatar/forums.pimoroni.com/tonypigram/32/9334_2.png) [@tonypigram](https://forums.pimoroni.com/u/tonypigram)\ **Post date:** [January 5, 2023, 9:51am UTC](https://forums.pimoroni.com/t/pico-demo-sd-card/21076/11 "2023-01-05T09:51:32Z")
I dug a bit deeper and whilst doing cmake I pass it the board type: cmake -D"PICO\_BOARD=vgaboard" … _(not sure why that shows as 3 dots - should be 2)_ which led me to find this file: /opt/pico-sdk/src/boards/include/boards/vgaboard.h that defined these values: // Note DAT1/2 are shared with UART TX/RX (pull jumpers off header to access // UART pins and disconnect SD DAT1/2) #define VGABOARD\_SD\_CLK\_PIN 5 #define VGABOARD\_SD\_CMD\_PIN 18 #define VGABOARD\_SD\_DAT0\_PIN 19 and I was using SD\_CS PIN 22 in my C code and spi1. Using these values I still cannot get it to initialise from C/C++, > _SD card mount file system failed ,error code :(3)_ so maybe you are right… it might not be SPI? In which case, are there any c/c++ examples out there that access the sd-card on the pico demo board? I cannot seem to find anything. I did find an example of someone [using the pico dvi board (hdmi version) and their code](https://github.com/fhoedemakers/pico-infonesPlus) doesn’t seem to do anything smart with the sdcard, so I’m a bit baffled - did I just get a broken board and I’ve been chasing my tail all along? ---
**Author:** ![bablokb](https://avatars.discourse-cdn.com/v4/letter/b/ee59a6/32.png) [@bablokb](https://forums.pimoroni.com/u/bablokb)\ **Post date:** [January 5, 2023, 10:33am UTC](https://forums.pimoroni.com/t/pico-demo-sd-card/21076/12 "2023-01-05T10:33:56Z")
I think you found the correct link (I failed). If you look at the source code, they implement SPI using PIO, i.e. they don’t use the hardware-spi function-blocks of the pico, but implement their own PIO-version. That’s why it is not relevant that the SD-CLK is not connected to a pico-spi-clk pin. You will find the code in the drivers/sdcard subdirectory. So the next step for you would be to try to integrate that code into your project. Would be great if this works. ---
**Author:** ![tonypigram](https://sea2.discourse-cdn.com/flex016/user_avatar/forums.pimoroni.com/tonypigram/32/9334_2.png) [@tonypigram](https://forums.pimoroni.com/u/tonypigram)\ **Post date:** [January 5, 2023, 3:48pm UTC](https://forums.pimoroni.com/t/pico-demo-sd-card/21076/13 "2023-01-05T15:48:26Z")
okay… I need bigger brains than I’ve got to figure this one out. I’ve uploaded the code to here: > **[pico\_c/picovga at main · pi-gram/pico\_c](https://github.com/pi-gram/pico_c/tree/main/picovga)** > > main/picovga It contains the libraries grafted into a super-simple app that attempts to initialise and mount the sdcard for the Pico demo VGA board. I’ve pasted my debug output into the sdcard\_test.c file, but will reproduce it here: SDCARD\_TEST.C: system init response=0 SDCARD\_TEST.C: SDCARD\_SPI\_BUS=1073987584 SDCARD\_TEST.C: SDCARD\_PIN\_SPI0\_CS=22 SDCARD\_TEST.C: SDCARD\_PIN\_SPI0\_SCK=18 SDCARD\_TEST.C: SDCARD\_PIN\_SPI0\_MOSI=19 SDCARD\_TEST.C: SDCARD\_PIN\_SPI0\_MISO=20 SDCARD\_TEST.C: SDCARD\_PIO=1344274432 SDCARD\_TEST.C: SDCARD\_PIO\_SM=0 SDCARD\_TEST.C: Let’s try to mount the SDcard FF.C: inside f\_mount about to call mount\_volume FF.C: about to call disk\_initialize from within mount\_volume SDCARD.C: about to call init\_spi() here, I think I was called by FF.C: mount\_volume SDCARD.C: we should be executing the PIO code here SDCARD\_TEST.C: SD card mount error: 3 SDCARD\_TEST.C: sdcard\_success=0 SDCARD\_TEST.C: Bugger an error happened…again… I put the filename on the front of the printf’s so I could trace through the logic of the code and make sure it was working as I thought it was. From what I can tell, it is indeed going through the correct steps… but still failing anyway. I’ve tried with: cmake … make and with the board specified: cmake -D"PICO\_BOARD=vgaboard" … make that doesn’t seem to make a difference. I’ve tried changing from sp1 to sp0, just incase it is on the first device, done the same with pio1 and pio0 - same result. Maybe I have a typo / assumption somewhere that is blazing obvious to someone else? but I think I’ve now tried everything I can to read an SDCard using the Pico demo VGA board, without success :-( The good news is… I don’t think the GPIO PIN settings is the problem :-D That appears to be okay. ---
**Author:** ![bablokb](https://avatars.discourse-cdn.com/v4/letter/b/ee59a6/32.png) [@bablokb](https://forums.pimoroni.com/u/bablokb)\ **Post date:** [January 6, 2023, 12:55pm UTC](https://forums.pimoroni.com/t/pico-demo-sd-card/21076/14 "2023-01-06T12:55:28Z")
I think your pins don’t match the wiring of the board: [https://cdn.shopify.com/s/files/1/0174/1800/files/vgademobase\_480x480.png?v=1617010535](https://cdn.shopify.com/s/files/1/0174/1800/files/vgademobase_480x480.png?v=1617010535) e.g. SD-CLK = Pin7 = GP5 = SDCARD\_PIN\_SPI0\_SCK SD-CMD = Pin24 = GP18 = SDCARD\_PIN\_SPI0\_MOSI I still have to figure out the other pins, they are labeled SD\_DAT0-SD\_DAT3 in the shop. But I somewhere have a SD-pinout which labels all the pins in both ways, so give me some time. ---
**Author:** ![tonypigram](https://sea2.discourse-cdn.com/flex016/user_avatar/forums.pimoroni.com/tonypigram/32/9334_2.png) [@tonypigram](https://forums.pimoroni.com/u/tonypigram)\ **Post date:** [January 6, 2023, 1:08pm UTC](https://forums.pimoroni.com/t/pico-demo-sd-card/21076/15 "2023-01-06T13:08:02Z")
You genius! SDCARD\_TEST.C: system init response=0 SDCARD\_TEST.C: SDCARD\_SPI\_BUS=1074003968 SDCARD\_TEST.C: SDCARD\_PIN\_SPI0\_CS=22 SDCARD\_TEST.C: SDCARD\_PIN\_SPI0\_SCK=5 SDCARD\_TEST.C: SDCARD\_PIN\_SPI0\_MOSI=18 SDCARD\_TEST.C: SDCARD\_PIN\_SPI0\_MISO=19 SDCARD\_TEST.C: SDCARD\_PIO=1345323008 SDCARD\_TEST.C: SDCARD\_PIO\_SM=0 SDCARD\_TEST.C: Let’s try to mount the SDcard FF.C: inside f\_mount about to call mount\_volume FF.C: about to call disk\_initialize from within mount\_volume SDCARD.C: about to call init\_spi() here, I think I was called by FF.C: mount\_volume SDCARD.C: we should be executing the PIO code here SDCARD.C: pio\_spi\_init executed SDCARD\_TEST.C: Mounted OKAY! SDCARD\_TEST.C: Current directory is: / SDCARD\_TEST.C: sdcard\_success=1 SDCARD\_TEST.C: Woo!hoo! party time ---
**Author:** ![bablokb](https://avatars.discourse-cdn.com/v4/letter/b/ee59a6/32.png) [@bablokb](https://forums.pimoroni.com/u/bablokb)\ **Post date:** [January 6, 2023, 2:36pm UTC](https://forums.pimoroni.com/t/pico-demo-sd-card/21076/16 "2023-01-06T14:36:18Z")
Glad it works! The real genius are the people that implemented that SPI-PIO stuff. I really have to spend some time with that technology one day. ---
**Author:** ![dkts2021](https://avatars.discourse-cdn.com/v4/letter/d/f08c70/32.png) [@dkts2021](https://forums.pimoroni.com/u/dkts2021)\ **Post date:** [May 21, 2024, 12:32pm UTC](https://forums.pimoroni.com/t/pico-demo-sd-card/21076/17 "2024-05-21T12:32:28Z")
Hi I have this lcd display with onboard sd card from waveshare [https://www.waveshare.com/pico-restouch-lcd-2.8.htm](https://www.waveshare.com/pico-restouch-lcd-2.8.htm) i can only access the sd card successfully using the library that waveshare provides. I think the two boards have similar pinout, but i get a … SDCARD\_TEST.C: SDCARD\_PIN\_SPI0\_CS=22 SDCARD\_TEST.C: SDCARD\_PIN\_SPI0\_SCK=5 SDCARD\_TEST.C: SDCARD\_PIN\_SPI0\_MOSI=18 SDCARD\_TEST.C: SDCARD\_PIN\_SPI0\_MISO=19 … SDCARD\_TEST.C: SD card mount error: 3 with the code from picovga repo I tried the [no-OS-FatFS-SD-SDIO-SPI-RPi-Pico](https://github.com/carlk3/no-OS-FatFS-SD-SDIO-SPI-RPi-Pico) library with no success. I can’t figure out what is wrong. Any idea? ---
**Author:** ![bablokb](https://avatars.discourse-cdn.com/v4/letter/b/ee59a6/32.png) [@bablokb](https://forums.pimoroni.com/u/bablokb)\ **Post date:** [May 21, 2024, 1:10pm UTC](https://forums.pimoroni.com/t/pico-demo-sd-card/21076/18 "2024-05-21T13:10:38Z")
The thread above is about a board that uses bitbang SPI over PIO. The Waveshare SD-card uses plain and simple hardware SPI.