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SPiCboard library (libspicboard, revision 14925) API documentation

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7SEG (Seven Segment Display)

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

Files

file  7seg.h
 

Functions

int8_t sb_7seg_showNumber (int8_t nmbr)
 prints a number in the range [-9; 99] on the 7-segment display More...
 
int8_t sb_7seg_showHexNumber (uint8_t nmbr)
 prints the hexadecimal representation of an 8-bit unsigned integer on the 7-segment display More...
 
int8_t sb_7seg_showString (const char *str)
 prints a 2 character string on the 7-segment display More...
 
void sb_7seg_disable (void)
 disables the 7-segment displays More...
 

Detailed Description

Controls the two 7-segment displays on the board.

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.

Note
As the timer-library is used, interrupts must be enabled for the display to work
See also
timer.h

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
nmbrthe number to print
Return values
0on success
!0on error
int8_t sb_7seg_showNumber ( int8_t  nmbr)

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

Parameters
nmbrthe number to print
Return values
0success
-1nmbr is smaller than -9
-2nmbr is greater than 99
int8_t sb_7seg_showString ( const char *  str)

prints a 2 character string on the 7-segment display

Supported characters are in the group [-_ 0-9A-Za-z] (contains space). Read this article for possible representations of these characters. Two characters of the set should never have the same representation. No differentiation is made between upper- and lowercase characters.

Parameters
strthe 0-terminated string
Return values
0success
-1character at position 0 not printable
-2character at position 1 not printable
-3both characters not printable
-4str is an empty string