AS3525-A/-B C22O22
Data Sheet, Confidential
7.3.12.5 DIN register
With the dinStrobe, data are written to the DIN register. This gives a simple mechanism, in which for example the status data can be read from a
LCD display interface.
To do a data read, first the START READ (strd) bit is programmed into the control register. With START READ, the control signal generator starts
to generate one cycle with the according control signals. Data are strobed by the programmed strobe time into the din register. After the cycle is
completed the HW resets the strd bit to 0. With set of the strd bit, the rd_data_valid bit is also reseted.
The SW just has to poll the rd_data_valid bit, when the bit gets set the input data can be read from the din register. After read cycle, the control
signal generator returns to the quiescent state.
Following timing diagram shows an example of three read cycles.
Figure 37 DBOP read cycle example
Read cycle 0
Read cycle 1
Read cycle 2
C0 (= read_n)
Data input
xx
D0
D1
D2
Read strobe
DIN register
strd
D0
D1
D2
rd_data_valid
Note: Be aware that the read cycle should only be activated when there is no active write cycle (FiFo is empty). Otherwise the results of such action
get unpredictable.
For any read cycle, the write enable bit must be set to 0 (write disabled).
start read
(strd)
write enable
(wen)
FiFo empty
Status
DBOP function
quiescent
quiescent
valid write
quiescent
valid read
valid read
valid write
quiescent
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
7.3.12.6 Interrupt Generator
Depending on the FiFo Status, an interrupt request can be generated. The conditions that cause an interrupt are set within the control register.
The interrupt output DBOPIRQ is active high.
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