Go_unconfigured( ) function, Syntax, Example – Echelon Neuron C User Manual
Page 107: High_byte( ) built-in function, Interrupt_control( ) built-in function
Neuron C Reference Guide
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go_unconfigured( )
Function
The go_unconfigured( ) function puts the device into an unconfigured state. It
also overwrites all the domain information, which clears authentication keys as
well.
The go_unconfigured( ) function can be used after detecting and logging a serious,
unrecoverable error. Some security devices also call this function when they
detect a attempt to tamper with the device, and thus render the device
inoperational and erase the secret authentication keys.
Syntax
#include <control.h>
void go_unconfigured (void);
Example
void f() {
...
if (unrecoverable) {
error_log(MY_UNRECOVERABLE_ERROR);
go_unconfigured();
}
}
high_byte( )
Built-in Function
The high_byte( ) built-in function extracts the upper single-byte value from the
a
double-byte operand. This function operates without regard to signedness. See
also low_byte( ), make_long( ), and swap_bytes( ).
Syntax
unsigned short high_byte (unsigned long
a
);
Example
short b;
long a;
void f(void)
{
a = 258;
// Hex value 0x0102
b = high_byte(a);
// b now contains the value 0x01
}
interrupt_control( )
Built-in Function
The interrupt_control( ) built-in function enables or disables interrupts. You can
call the interrupt_control( ) function at any time to enable or disable one or more
of the three interrupt types: I/O interrupts, timer/counter interrupts, or periodic
system timer interrupts. This function applies only to the hardware interrupts