DIO

The DIO (General Purpose IO) can be input or output as desired under the control of the firmware.

The following can be done with general purpose IO:

• Digital input (H or L level readout)
  • Pull-up (50kΩ, typ) can be set.
• Digital output (H or L level output)
  • The maximum value of the supply or suction current (3 mA at 3 V typ).
• Interrupt (rising or falling)
  • The rise and fall cannot be detected simultaneously.
  • It is also available in sleep mode.

About port numbers

There are 20 DIOs, numbered 0 to 19. These are called in order DIO0 … DIO19. The following APIs allow you to specify the DIO number directly.

vPortAsInput(10); // set DIO10 as input
bool_t bPort = bPortRead(10);
   // TRUE: DIO10 is LO(GND) level
   // FALSE: DIO10 is HIGH(VCC) level

About negative logic

For TWELITE wireless microcontrollers, the port state at power-on reset is at the High (Vcc) level, so in principle TWELITE NET sets the High (Vcc) level to 0 and the Lo (GND) level to 1.

State at start-up

On power-up, all ports are initialised in the following state

• Input
• Pull-up enabled

Input

To change a port to an input, call vPortAsInput().

#define PORT_DI1 11 // DIO11
vPortAsInput(PORT_DI1);

To read the status of a port, call bPortRead().

bool_t bPortStat;
bPortStat = bPortRead(PORT_DI1);

Output

To change the port to an output, call vPortAsOutput(c). Also, to set the value of a port, call vPortSetLo(), vPortSetHi(), or vPortSet_TrueAsLo().

#define PORT_DO1 18 // DIO18
vPortSet_TrueAsLo(PORT_DO1, TRUE); // TRUE: set Lo
vPortAsOutput(PORT_DO1);

Pull-up

You can stop the pull-up by calling vPortDisablePullup().

#define PORT_DI1 11 // DIO11

vPortDisablePullup(PORT_DI1);
vPortAsInput(PORT_DI1);