TC1796
Peripheral Units (Vol. 2 of 2)
Analog-to-Digital Converter (ADC)
User’s Manual
25-29
V2.0, 2007-07
ADC, V2.0
25.1.3
Conversion Request Arbitration
Because several conversion request sources can generate conversion requests at the
same time, an arbitration mechanism is implemented in order to detect the conversion
request source and channel with the highest priority.
shows the arbitration
scheme with the associated controls.
Figure 25-17 Arbitration
Arbitration of pending conversion requests is performed according to the following two
stage prioritization algorithm:
•
Source arbitration
is the first stage in the arbitration algorithm. Starting with the
conversion request source “Auto-Scan” up to “Channel Injection”, each source is
checked if its arbitration participation flag is set. If the participation flag is set and its
priority is higher than the priority of the other selected sources, that source is the
winner of the arbitration.
MCA06020
Channel Injection
CHIN or Back-Up
QUEUE0 or Back-Up
Timer
TTC[15:0]
External Event
EXCRP[15:0]
Queue
Auto-Scan
ASCRP[15:0]
Winning Source
Analog Channel
Channel Injection
SALCHIN
CHP
Timer
SALT
TP
Software
SWCRP[15:0]
Queue
Auto-Scan
Source
Software
SALSW0
SW0P
SALQ
QP
SALAS
ASP
Priority
Participation
Winning Source
Winning Channel
Source
Arbitration
External Event
SALEXT
EXP
Select
Channel
Arbitration