AK7755EN_16 Datasheet, PDF (77/109 Pages) Asahi Kasei Microsystems – DSP with Mono ADC Stereo CODEC + Mic/Lineout Amp

[AK7755]
7-3. External Conditional Jump
External Conditional Jump Code Writing (during System Reset and RUN)
(1) COMMAND
0xF4
(2) DATA
D7~D0
External Conditional Jump code can be input during both DSP Reset and RUN. Input data is set to the
designated register on the rising edge of LRCKO. The RDY pin changes to “L” when the command code
is transferred, and it changes to “H” when write operations are completed. When any single bit of “1”
data in 8-bit External Jump code matches an “1” bit data in the IFCON field, a Jump instruction is
executed. Then, the RDY pin changes to “H” when the rise of LRCKO is captured. Access operation by
microcontroller is prohibited until the RDY pin changes to “H”. IFCON field is the area where the
external conditions are written. This Jump code is reset to 00h by setting the IRSTN pin to “L”, but it is
not reset by System Reset.
76543210
External Conditional Jump Code
■■■■■■■■
↑
Check if “1” of IFCON field corresponds with External Conditional Jump including Jump pins
by at least one at the same location.
7
↓
0
IFCON Field

External Conditional Jump Code
■■■■■■■■
DSPRESETN bit
SCLK
don’tcare
SI ^(L/H)
CSN
LRCK
F4h
D7…D0
don’tcare
(L/H)
RDY
Next command write is available
Figure 58. External Conditional Timing in System Reset (SPI)
DSPRESETN bit
SCLK
SI
don’tcare
(L/H)
F4h
D7 … D0 ^{don’tcare}
(L/H)
CSN
LRCK
RDY
Figure 59. External Conditional Jump Timing during RUN (SPI)
014006643-E-00
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