The IOTester^® functions

The IOTester^® tool and external I/O hardware is operated via a few functions for basic I/O register access plus a few initialization functions:

 // I/O register access functions
 unsigned long iot_rd( unsigned long addr);            // Read from I/O register 
 void iot_wr(  unsigned long addr, unsigned long dat); // Write to I/O register
 void iot_or(  unsigned long addr, unsigned long dat); // Do OR  operation on I/O register (set bit)
 void iot_and( unsigned long addr, unsigned long dat); // Do AND operation on I/O register (clear bit)
 void iot_xor( unsigned long addr, unsigned long dat); // Do XOR operation on I/O register (invert bit)

 // I/O register array access functions (buffer access functions)
 unsigned long iot_rdbuf( unsigned long addr, unsigned long index);               
 void iot_wrbuf(  unsigned long addr, unsigned long index, unsigned long dat); 
 void iot_orbuf(  unsigned long addr, unsigned long index, unsigned long dat); 
 void iot_andbuf( unsigned long addr, unsigned long index, unsigned long dat); 
 void iot_xorbuf( unsigned long addr, unsigned long index, unsigned long dat); 

 // Initialization and exit functions
 int iot_init(unsigned long device);                   // Init connection to IOTester device
 void iot_exit(void);                                  // Close connection to IOTester device (optional)

Use of these functions are illustrated in the following examples.
Note: All IOTester specific functions have the name prefix iot_.
The portable iohw syntax for I/O register access is supported as well.

Example: "Single chip mode"

The program example configures IOTester for "single-chip mode", and do some pin read and write operations.
All 45 IOTester signals are I/O pins. Only internal IOTester registers are accessible from the PC application.
In the example 1 pin is configured as output. The other pins are inputs (default).
Register names and addresses for all internal IOTester devices are predefined in <iotester.h>

#include <iotester.h> // Define IOTester functions and symbolic names for internal registers
#include <stdio.h>    // printf(..) used for test message on the PC screen

// Define connector pins for the test
#define TEST_OUT_PIN  IOT_J1_PIN1
#define TEST_IN_PIN   IOT_J1_PIN2

// Read pins and use the PC screen to monitor the "embedded" hardware states
void report_pin_levels(void)
   {
   unsigned long J1pins;
   // Read pin levels directly (independent of wether a pin is input or output) 
   J1pins = iot_rd( IOT_INPUT_REG1 );
 
   // Show pin values on PC screen. 
   // Test pins: Short circuit pins on the connector and see the Out and In values track
   printf("\nOut pin = %d, In pin = %d",
      (J1pins & TEST_OUT_PIN) ? 1 : 0,
      (J1pins & TEST_IN_PIN)  ? 1 : 0);
   }

int main(void)
   {
   int i;
   // Init IOTESTER driver, search for any IOTester connected to the PC
   if ( iot_init(0) )
      return 1; // Could not connect
 
   // IOTester connection OK

   // Configure IOTester for I/O mode only (no devices or external bus)
   iot_wr( IOT_PIN_MODE_REG, 0);

   // All pins are input as default
   // Configure test pin for output without pull up.
   iot_wr( IOT_IOSET_REG1,    TEST_OUT_PIN ); // Logic high, but no drive yet
   iot_wr( IOT_IODIRSET_REG1, TEST_OUT_PIN ); // Pin = output, drive active
   iot_wr( IOT_IOPUPCLR_REG1,~TEST_OUT_PIN ); // Clear passive pull up
 
   // Loop toggling pin low and high
   for (i=0; i<1000; i--)
       {
       // Test Pin is active low
       iot_wr( IOT_IOCLR_REG1,~TEST_OUT_PIN );
       report_pin_levels();

       // Test Pin is active high 
       iot_wr( IOT_IOSET_REG1, TEST_OUT_PIN );
       report_pin_levels();
       }
 
   // Release all IOTester resources
   iot_exit();
   return 0;
   }

Links to:
IOTester tool description
Example 1: Start using IOTester I/O port pins - "Single chip mode"
Example 2: Enabling the External bus
Example 3: Using Internal Devices and External bus.
Example 4: Using Target Interrupt.
Example 5: Writing portable I/O driver source code with <iohw.h>
Example 6: <iohw.h> implementation methods and definition of I/O registers
Example 7: Swapping source code between PC and target platforms