Figure 16.4B Flow Chart Of Data Protection Function - Fujitsu F2MC-16LX MB90580 Series Hardware Manual

(5) Conversion data protection
The A/D converter has a conversion data protection function that enables continuous conversion and
preservation of multiple data items using I
Since there is only one conversion data register, its value is updated each time conversion is com-
pleted. Thus, continuous data conversion results in the loss of the previous data due to storage of the
new data. To prevent this situation, the A/D converter pauses after conversion if the previous data item
has not been transferred to memory by I
transferred to memory.
The pause is released after data is transferred to memory by I
If the previous data has been transferred to memory, the A/D converter continues operation without
pausing.
Note: * This function is related to the INT and INTE bits of ADCS2.
The data protection function operates only when interrupts are enabled (INTE=1).
If interrupts are disabled (INTE=0), this function is disabled. Continuous A/D conversion results in loss of
previous data, since the converted data items are saved to the register one after another.
2
If I OS is not used while interrupts are enabled (INTE=1), the INT bit is not cleared. Thus, the data
tection function works and the A/D converter pauses. In this case, clearing the INT bit in the interrupt
sequence releases the pause.
If the A/D converter is pausing during I
this case, the value in the conversion data register may be changed without being transferred.
Restarting the A/D converter while it is pausing destroys the standby data.
Flow of data protection function (when I
Setting I
Starting continuous A/D conversion
Ending first conversion
Saving the result in the data register
Ending second conversion
End I
Saving the result in the data register
Ending third conversion
Ending the last conversion
End
MB90580 Series
2
OS operation, disabling interrupts may restart the A/D converter. In
2
2
OS
NO
2
OS?
YES
Continued
Interrupt routine

Figure 16.4b Flow Chart of Data Protection Function

2
OS.
2
OS. The converted data is not saved until the previous data is
OS is used)
The flow while A/D converter is stopped is omitted.
*1: Restarting the converter while paused destroys
the standby conversion data.
Pausing A/D conversion
YES
Stooping A/D conversion
2
OS.
2
Starting I OS
NO
2
End I OS?
2
Starting I OS
2
Starting I OS
Chapter 16: A/D Converter
16.4 Operations
pro-
*1
233