GPIO can be used as input/output port?

Question

I am trying to comunicate with Temp/Humid module DHT11 However data pin should be pull up to 3.3 but while my RTL trying to comunicate with DHT11 throgh IO13 pin, Data line pull down to GND. if GPIO can be inout port, then any one know how? 
 My RTL working fine in simulation with Vivado

embeddedguy · Answer

As you are using DHT11 sensor, you should use Serial protocol i.e. UART RX line to sample the received values. 
 The DHT11 sensor works like following. 
 "Data line remains in high normally, then master in this case FPGA will start communication first. The the sensor will respond with temparature, humidity data". 
 See the following image of timing diagram.

The output given out by the data pin will be in the order of 8bit humidity integer data + 8bit the Humidity decimal data +8 bit temperature integer data + 8bit fractional temperature data +8 bit parity bit. To request the DHT11 module to send these data the I/O pin has to be momentarily made low and then held high as shown in the timing diagram below 
 
 components101.com/.../dht11-temperature-sensor

GPIO can be used as input/output port?

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