Top microcontroller threads on EDAboard.com – June

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Stuck in ISR, RCIF is not firing when UART with PIC18f5420 and SIM800 – I am new to PIC, I am able to transmit through PIC18f4520 and SIM800 but could not able to receive it. I run a debugger, but the program is stuck in ISR but RCIF is not fired at all. Read more

UART to USB converter – I am wondering how to use MCP2221 for UART to USB with a microcontroller. I would have UART on the microcontroller side which I would like to connect to MCP2221 to convert the protocol to USB. Read more

Resolver output validation – I need to validate the resolver output. The communication with the master controller is through SPI. But I am not sure how to validate that data. The SPI data consists of position and velocity. The resolver is AD2S1210. Read more

Error in Keil micro vision –  what is the meaning of “error: preprocessor :MACRO TOO NESTED. Read more

SD card MBR interpretation issue – I am interfacing an SD card on ARM: LPC3250.On issuing READ_SINGLE_BLOCK(CMD17) command i am getting MBR output as below.
data[0] = 0x00000000
…..
data[110] = 0x00000000
data[111] = 0x02000000
data[112] = 0x3D06000A
data[113] = 0x0087BDFD
data[114] = 0xEF790000
data[115] = 0x0000003A
data[116] = 0x00000000
……….
data[127] = 0xAA550000

I am Interpreting above output i.e 0x00000087*512 = 0x10E00. (Relative/Boot sector address) as per SDCardmap. But when I open my 2GB SD card in Hex Editor Neo MBR is not visible, I am seeing BOOT sector at address 0x0000 attached snap below

and @address 0x10E00 all the bytes are 0 snap below

1) why MBR is not visible in Hex Editor Neo?
2) Why MBR pointing to 0x10E00 location but boot sector start at location 0x0000 ?
3) I am using example code of LPC3250 initialize and read command sequence looks fine.

I tried both SDFormatter tool and Windows format Default/Fat16/Fat32, 4 different 2GB SD card of Transcend. Read more

Port 4 for SST89E516RD2 – I am working on a project where I have to use an SST89E516RD2 microcontroller. I am using Keil as a programming software. I am using 44 PIN TQFP SMD package When I try to build the program in keil I am getting an error (35):
error C146: ‘P4’: invalid base address

I have even modified the startup file and added:

sfr   P4  = 0xA5;

as per the address mentioned in the datasheet page 20.
so I need to modify something else to use this port4.

Read more

Clarification on the SPI communication – If the user application does not change the data in the SPIxBUF register, every new transmission shifts the SPIxBUF register value instead of shifting the value received in the shift register. What does it mean? I cannot send a constant value like 0x02 continuously. Do I need to keep changing or toggling the data? Read more

MikroC delay using interrupt – I am trying to implement a delay using timer0 interrupt. I’ll just post an abstraction of the code in MikroCc. The code does not work as I expected. Can somebody please point out the mistake I am making or suggest a better way for achieving a 100 ms delay using interrupt? Read more

How to use if condition in switch statement – What does an if statement do within switch statement. I want apply if condition for following task

first case if (task=task1)
second case if (task=task2)
third case if (task=task1)
Read more