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9 years, 10 months ago.
How to use printf over usb-serial ?
Hi,
I bought this board http://international.switch-science.com/catalog/1714/
But I don't know how to print over usb serial, such that I can see output on terminal when I connect it to usb.
Here is my code
#include "mbed.h"
#define ADR 0x58
I2C i2c( dp5, dp27 ); // sda, scl
Serial pc(dp16, dp15); // tried dp15,dp16 and dp16,dp15 and USBTX, USBRX
int main() {
pc.baud(115200);
i2c.frequency(100000);
char v;
char cmd = 0x00;
pc.printf("Loop\r\n");
while(1) {
pc.printf("Loop\r\n");
i2c.write( ADR, &cmd , 1);
i2c.read( ADR, &v, 1 );
wait(1);
//pc.printf("v = %d %%\t", v);
}
}
I hope this board does not need extra USB-Serial adapter, that actually kills the point of paying for it. Would be nice if someone could explain why it does not work.
Thanks
Question relating to:
2 Answers
9 years, 10 months ago.
I tried to test UART with this code,
#include "mbed.h"
Serial pc(dp16, dp15); // tx, rx
int main() {
pc.baud(9600);
while (1) {
wait(5);
pc.printf("Hello World!\r\n");
}
}
And it works. I'm not sure why your LPC1114FN28 is keeping silent. If you could, could you try to erase flash?
You can erase flash with SWD or ISP. When you want to use SWD, you can use CMSIS-DAP with MDK-ARM. When you want to use ISP, you may need USB-UART bridge and Flash Magic. I wrote brief instruction about ISP. https://mbed.org/users/ytsuboi/notebook/getting-started-with-mbed-lpc1114/
-
2014-06-21 Update
Sorry I kept you waiting so long. Probably, this issue was solved by today's fix. Please try latest firmware. https://mbed.org/teams/Switch-Science/wiki/Firmware-LPC1114FN28
(1) Can you please try this code ?
#include "mbed.h"
#define ADR 0x58
I2C i2c( dp5, dp27 ); // sda, scl
Serial pc(dp16, dp15); // tried dp15,dp16 and dp16,dp15 and USBTX, USBRX
int main() {
pc.baud(115200);
i2c.frequency(100000);
char v;
char cmd = 0x00;
pc.printf("Loop\r\n");
while(1) {
pc.printf("Loop\r\n");
i2c.write( ADR, &cmd , 1);
i2c.read( ADR, &v, 1 );
wait(1);
//pc.printf("v = %d %%\t", v);
}
}
After running this one, serial stopped working (I didn't physicaly touch chip, that worked before flashing this I2C code).
(2) Is it possible to erase with bus-pirate or bus-blaster ?
Thanks, Mateusz
posted by 09 Jun 20141) What I2C device did you connect?
2) I'm not sure bus-pirate is enough to use ISP. I used FTDI Breakout.
Oops, I remember you are using Linux. So, you can use ISP with lpc21isp. http://sourceforge.net/projects/lpc21isp/
Dear Yoshihiro,
1) There is nothing connected to the chip, besides USB cable to program it at the moment. Just flashing this code, that does something with I2C, and the chip became silent.
2) I will try that if I figure out how to. At this moment the link you gave, does not contain instructions how to erase the chip, but only that there is a possibility of using isp and command you used to flash hex file.
posted by 09 Jun 2014I found a problem, maybe on Drag&Drop programing function. It may need a time to solve this bug.
If you want quick solution, please export your project from online compiler to Keil uVision 4. And try to build and flash with uVision 4 via interface's CMSIS-DAP function. You can use uVision 4 for free if the target binary is less than 32kB. https://www.keil.com/demo/eval/armv4.htm
I followed instruction how to update firmware, and no I don't see mbed folder to drop program. I can enter in ISP mode to CRD DISABLED folder, but nothing else works now.
posted by 21 Jun 2014I added instruction for Linux. Please update the interface firmware. https://mbed.org/teams/Switch-Science/wiki/Firmware-LPC1114FN28
posted by 21 Jun 2014
9 years, 10 months ago.
The board has a lpc11U35 that functions as serial to USB interface. The dp15,dp16 pair is the serial port for the USB interface. However, you may want to check that two solder bridges (SJ1, SJ2) are in place to actually connect the LPC1114 serial port to the USB interface. Obviously you also need to install the mbed windows serial driver and check the device drivers on the PC to make sure everything has installed correctly.
Well I actually can flash the chip so it I think that happens via dp16/dp15 right ? Bridges are connected, I checked schematics. Also I am not using Windows, but GNU/Linux and gtkterm. I know my terminal works with bus pirate, I don't know why I dont see anything from this lpc1114 though.
Even this simple example does not show anything after pressing reset.
#include "mbed.h"
//Serial pc(USBTX, USBRX); // tx, rx
Serial pc(dp16, dp15); // tx, rx
int main() {
pc.printf("Hello World1!\n");
printf("Hello World2!\n");
}
Oops. I've never tested HDK (the interface firmware) with Linux... As well as I know, UART bridge function with OS X have some trouble. I'm so sorry for the inconvenience.
posted by 08 Jun 2014Assigned to 9 years, 10 months ago.
This means that the question has been accepted and is being worked on.
.
posted by Mateusz Kaduk 08 Jun 2014Sorry I kept you waiting so long. Probably, this issue was solved by today's fix. Please try latest firmware. https://mbed.org/teams/Switch-Science/wiki/Firmware-LPC1114FN28
posted by Yoshihiro TSUBOI 21 Jun 2014Your update instructions do not mention that firmware.bin should be overwritten.
mateusz@astro:$ dd bs=1024 conv=nocreat,notrunc if=/Desktop/lpc11u35_lpc1114_if_2014062100.bin of=/media/mateusz/CRP\ DISABLD/firmware.bin 32+1 records in 32+1 records out 32892 bytes (33 kB) copied, 0.107167 s, 307 kB/s mateusz@astro:$
Now I can see mbed folder, and my code works. Thanks,
posted by Mateusz Kaduk 21 Jun 2014Nice. I'm guessing the point is using dd. Anyway, thanks for your cooperation.
posted by Yoshihiro TSUBOI 21 Jun 2014