[Solved] Can't place output on pin 28 and 29 of Tang Nano, but LCD example design do.

Hi,
I’m trying to modify the blinking led example to map led on other pin of Tang Nano.
To do that I changed the led_prj.cst pinout file like it :

IO_LOC “sys_clk” 35;
IO_LOC “sys_rst_n” 15;

IO_LOC “led[0]” 27;
IO_PORT “led[0]” IO_TYPE=LVCMOS33;
IO_LOC “led[1]” 28;
IO_PORT “led[1]” IO_TYPE=LVCMOS33;
IO_LOC “led[2]” 29;
IO_PORT “led[2]” IO_TYPE=LVCMOS33;

//IO_LOC “led[0]” 16;
//IO_LOC “led[1]” 17;
//IO_LOC “led[2]” 18;

But I get place&route critical warning with it :

Warning (PR2028) : The constraint location is useless in current package.

Warning (PR2017) : ‘led_obuf126’(INS_OBUF) can’t be placed according to Constraint, because the Constraint location is a Dedicated Pin.

Warning (PR2028) : The constraint location is useless in current package.

Warning (PR2017) : ‘led_obuf127’(INS_OBUF) can’t be placed according to Constraint, because the Constraint location is a Dedicated Pin.

I wonder why it’s working onLCD example (there are output plugged on this pins)

IO_LOC “LCD_R[0]” 27;
IO_LOC “LCD_R[1]” 28;
IO_LOC “LCD_R[2]” 29;

and not in LED example ?
I have gowin fpga ide version 1.9.2.

those pins are " Dedicated Pin."
you need disable its " Dedicated Function" in IDE setting, then you can use it as normal pins

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Thank @Zepan that was exactly my problem.
Solved \o/

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