7seg.h File Reference

Controls the two 7-segment displays on the board. More...

#include <stdint.h>

Go to the source code of this file.

Functions
int8_t	sb_7seg_showNumber (int8_t nmbr)
	prints a number in the range [-9; 99] on the 7-segment display
int8_t	sb_7seg_showHexNumber (uint8_t nmbr)
	prints the hexadecimal representation of an 8-bit unsigned integer on the 7-segment display
int8_t	sb_7seg_showStr (char *str)
	prints a 1-2 character string on the 7-segment display
void	sb_7seg_disable (void)
	disables the 7-segment displays

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Detailed Description

Controls the two 7-segment displays on the board.

Version:

$Rev: 149 $

The two 7-segment displays of the SPiCboard share one common port of the MCU. The two displays can be connected and disconnected from the port using two transistors. By quickly and periodically connecting and disconnecting the displays an observer will not be able to notice when a display is disabled and both displays can be used apparently simultaneously.

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Function Documentation

void sb_7seg_disable

(

void

)

disables the 7-segment displays

Any running alarms are unregistered.

int8_t sb_7seg_showHexNumber

(

uint8_t

nmbr

)

prints the hexadecimal representation of an 8-bit unsigned integer on the 7-segment display

Parameters:

nmbr

the number to print

Returns:

0 on success, negative value on error

int8_t sb_7seg_showNumber

(

int8_t

nmbr

)

prints a number in the range [-9; 99] on the 7-segment display

Parameters:

nmbr

the number to print

Returns:

0 on success, negative value on error

Return values:

	0	success
	-1	nmbr is smaller than -9
	-2	nmbr is greater than 99

int8_t sb_7seg_showStr

(

char *

str

)

prints a 1-2 character string on the 7-segment display

Supported characters are in the group [-_ 0-9ACE-JLPRSUXb-dhnoru] (contains space). Read this article for possible representations of these characters. Two characters of the set should never have the same representation.

Parameters:

str

the 0-terminated string

Returns:

0 on success, negative value on error

Return values:

	0	success
	-1	character at position 0 not printable
	-2	character at position 1 not printable
	-3	both characters not printable
	-4	str is an empty string