ice40up5k: cell type 'SB_IO_OD' is unsupported

[cwolpert]

Hi, I want to configure ice40UP5K's RGB pins as user IOs, similar to what is described in Annex B in TN1288 "iCE40 LED Driver Usage Guide" from lattice and the test code I found on https://github.com/YosysHQ/icestorm/blob/master/icefuzz/tests/sb_io_od.v. This is my module:

// configure ice40UP RGB IOs as GPIOs
// iCE40 LED Driver Usage Guide
module rgb_as_gpio(input a, output o1);
    wire o1i;

    assign o1i = a;

    SB_IO_OD #(
        .PIN_TYPE(6'b010001),
        .NEG_TRIGGER(1'b0)
    ) IO_PIN_I (
        .PACKAGEPIN(o1),
        .LATCHINPUTVALUE(),
        .CLOCKENABLE(),
        .INPUTCLK(),
        .OUTPUTCLK(),
        .OUTPUTENABLE(),
        .DOUT0(o1i),
        .DOUT1(),
        .DIN0(),
        .DIN1()
    );
endmodule

I instantiate it with "rgb_as_gpio RGB0 (.a(micout_r), .o1(AUD_R));", however nextpnr complains:

ERROR: cell type 'SB_IO_OD' is unsupported (instantiated as 'RGB0.IO_PIN_I')

I got the same error with lattice's original code from the above mentioned TN.

Could someone help me please?

[daveshah1]

For now just use the RGB pins like any other IO as a workaround (I will add SB_IO_OD to my todo list, it was supported by arachne but never moved across to nextpnr)

[pablogs9]

Same issue here, I have a kind of offtopic question. I forget to add the pull-up resistors so these RGB open-drain pins are not working in my design (I'm using them as GPIO). Is there any chance of enabling an internal pull-up?

Thanks!

[cwolpert]

Hi pablogs9, according to TN1288 there are no pull-ups for those RGP GP(I)Os. I forgot them as well and had to rework my PCB. But now these outputs are working fine. I'm using one the 3 pins as input, that one is working well, too. Cheers, Chris