Specifications

Digi m10 Hardware Reference v 1.20
Digi International, Inc. © 2009
Page 13 of 36
2.4.1 Powering Up
To power on the Digi m10, the host controller must provide an input voltage between 9 V and 18
V DC and then set the PWR_EN pin to active high. Typically, the Digi m10 will take two seconds
to be in a ready state. After powering on, the Digi m10 will toggle the DA pin once to let the host
controller know that it is ready to receive serial commands.
After the DA pin's initial toggle, its subsequent active high state indicates messages from the
satellite that are available in the Digi m10's inbound (IB) queue. The Digi m10's timing diagram for
powering up is shown in
Figure 4.
Figure 4: Timing Diagram for Powering Up
The delay between PWR_EN going high with respect to VCC going high is not critical. Digi
International recommends a 10 milliseconds delay.
2.4.2 Powering Down
The host controller can power down the m10 by setting the PWR_EN pin to LOW. The host
controller can leave the supply voltage for Digi m10 ON, or remove it at its discretion. If the supply
is left ON with PWR_EN set to low, the Digi m10 will be powered down. However, it will consume
a leakage current of less than 3 µA. The timing diagram of the Digi m10's power down sequence
is shown in
Figure 5.