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8 years, 6 months ago. This question has been closed. Reason: Off Topic
multi-sector sd card read stops after 33 sectors
I am using sd card manipulation in RAW data (i.e. no file system). And for read and write the only software i found is https://developer.mbed.org/users/cicklaus/code/FinalProgram/ from which i took only SDCard.h and SDCard.cpp.
The problem is that the multi block read (specific method of SDCard.cpp) does not work so i thought i can test it another way: in a for loop i am doing single sector read for the next 100 sectors. What i am not understanding is the code stops after reading 33 sectors. Can someone help me in that. Why cant i read as much sectors as i need?
the code i wrote is:
#include "mbed.h" #include "SDCard.h" #include <string> #include <string> Serial pc(SERIAL_TX, SERIAL_RX); SDCard sd(PA_7, PA_6, PA_5, PB_6, "sd"); std::string convertToString(unsigned char newdata) { std::string str; str.append(reinterpret_cast<const char*>(newdata)); return str; } std::string convertToString(unsigned char* newdata) { std::string str; str.append(reinterpret_cast<const char*>(newdata)); return str; } int main() { pc.baud(115200); for(int i=3; i>0; i--) { pc.printf("Wait %i seconds..\r\n",i); wait(1); } unsigned int baseddress = (unsigned int) (0x0001A000); for (int i = 0; i < 100; i++) { if (i != 0 && i % 8 == 0) { pc.printf("waiting before read chunk: %d ... \n", i); wait(1); } unsigned int newaddress = baseddress + i * 512; unsigned char* newdata = new unsigned char[512](); unsigned char result = sd.Read(newaddress, newdata); std::string str = convertToString(result); pc.printf(("Read result : <" + str + ">\n").c_str()); str = convertToString(newdata); pc.printf(("Read Content: %X : <" + str + ">\n").c_str(), newaddress); } }
p.s. If anyone can point me to other examples/libs i can use for the sdcard manipulation in RAW format it would be great.