Response To Power-On - Fujitsu MPG3XXXAH 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:
PDIAG- signal: Negated within 1 ms and asserted within 30 seconds, then negated within 31
Master device
Power On Reset-
Status Reg.
BSY bit
Slave device
Power On Reset-
BSY bit
PDIAG-
DASP-
6 - 2
Asserted within 400 ms, and negated after the first command is received from
the host or within 31 seconds or after executing software reset, which ever
comes first.
seconds.
Power on
Checks DASP- for up to
450 ms.
Max. 1 ms.
Figure 6.1 Response to power-on
C141-E112-01EN
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.
Max. 31 sec.