Response To Power-On - Fujitsu MPB3021AT Product Manual

6.1.1

Response to power-on

After the master device (device 0) releases its own power-on reset state, the master device
shall check a DASP- signal for up to 450 ms to confirm presence of a slave device (device 1).
The master device recognizes presence of the slave device when it confirms assertion of the
DASP- signal. Then, the master device checks a PDIAG- signal to see if the slave device has
successfully completed the power-on diagnostics.
If the master device cannot confirm assertion of the DASP- signal within 450 ms, the master
device recognizes that no slave device is connected.
After the slave device (device 1) releases its own power-on reset state, the slave device shall
report its presence and the result of power-on diagnostics to the master device as described
below:
DASP- signal: Asserted within 400 ms.
PDIAG- signal: Negated within 1 ms and asserted within 30 seconds.
Master device
Power On Reset-
Status Reg.
BSY bit
Slave device
Power On Reset-
BSY bit
PDIAG-
DASP-
6 - 2
Power on
Checks DASP- for up to
450 ms.
Max. 1 ms.
Figure 6.1

Response to power-on

C141-E045-02EN
Max. 31 sec.
If presence of a slave device is
confirmed, PDIAG- is checked for
up to 31 seconds.
Max. 30 sec.
Max. 400 ms.