STM32 output connected to 3v3 converter only goes from 2.58 to 3.19vdc

[Build-A-Burger]

I have another processor card with 3v3 output I've put on the same 3v3 converter and I get a clean 5vdc out the other end. I'm using STM32CubeMX to generate the code and I set the pins to output & GPIO_PULLUP. I've tried changing them to GPIO_NOPULL, GPIO_PULLDOWN too. I also measured the output on both a meter and scope without being connected to the 3v3 converter and its a clean signal. There is nothing on the output of the coverter when I'm doing this. Here's the standard code to configure the pins generated by CubeMX:

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Code C# - [expand]
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GPIO_InitTypeDef GPIO_InitStruct = {0};
    HAL_GPIO_WritePin(GPIOB, DS1620_PIN_DQ | DS1620_PIN_CLK | DS1620_PIN_RST, GPIO_PIN_RESET);
    GPIO_InitStruct.Pin = DS1620_PIN_DQ | DS1620_PIN_CLK | DS1620_PIN_RST;
    GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
    GPIO_InitStruct.Pull = GPIO_PULLUP;
    GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
    HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);

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If you want to see the rest of the code (there's a lot) I can put it up on github.

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I now have the entire project up on github.com:

https://github.com/sunbelt56/DiscoveryVL3

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I've tried taking the wire loose from the converter and measuring the voltage and it's always either 0 or 2.79 volts. Is this enough to drive a 3v3 converter? Could the output not have enough current? I've also tried a 4k7 pulldown resistor.

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OK - never mind. I lied when I said it was generated by CubeMX. I had copied it to a separate function and from the above code, it should be obvious what I did wrong.

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Here's the correct code, FYI:

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Code C# - [expand]
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GPIO_InitTypeDef GPIO_InitStruct = {0};
    HAL_GPIO_WritePin(GPIOB, DS1620_PIN_DQ | DS1620_PIN_CLK | DS1620_PIN_RST, GPIO_PIN_RESET);
    GPIO_InitStruct.Pin = DS1620_PIN_DQ | DS1620_PIN_CLK | DS1620_PIN_RST;
    GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
    GPIO_InitStruct.Mode = GPIO_PULLUP;
//  GPIO_InitStruct.Pull = GPIO_NOPULL;
//  GPIO_InitStruct.Pull = GPIO_PULLDOWN;
    GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
    HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);

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[KlausST]

Hi,

It's not clear to me.

What is a "3V3 converter"?
Show your circuit with exact part names. Hand drawn is OK.

And tell us exactly at which node you measured the voltage.

Klaus