Extended At Commands - Sierra Wireless MC5725 Hardware Integration Manual

CDMA and GSM / UMTS Mini Card Hardware Integration Guide
68
In the event of a discrepancy in values between this guide and the Product Specification Document (PSD), the PSD takes precedence.
necessary could decrease signal rise time, increase load
impedance, and cause USIM certification failure.
Putting an optional decoupling capacitor at XIM_VCC near
•
the USIM socket is recommended—the longer the trace
length (impedance) from the socket to the module, the
greater the capacitance requirement to meet compliance
tests.
Putting an optional series capacitor and resistor termination
•
(to ground) at XIM_CLK at the USIM socket to reduce EMI
and increase signal integrity is recommended if the trace
length between the USIM socket and module is long—47 pF
and 50 Ω resistor are recommended.
• Protect the USIM socket to make sure that the USIM cannot
be removed while the module / host device is powered up.
For example, you could place the socket under the battery
(for portable devices); consider similar options for other
device types.
• Test your first prototype host hardware with a Comprion
3
IT USIM test device at a suitable testing facility.

Extended AT commands

Several proprietary AT commands are available for the
MC57xx and MC87xx to use in hardware integration design
and testing (these commands are NOT intended for use by end
users). Refer to CDMA Extended AT Command Reference
(Document 2130621) for the MC57xx, or MC87xx Modem
Extended AT Command Reference (Document 2130616) for the
MC87xx for a list of all available commands and descriptions
of their functionality.
Some useful commands for use in hardware integration are
listed in Table 5‐4 (MC57xx) and Table 5‐5 (MC87xx).
Table 5-4: MC57xx Extended AT commands
Command
Internal commands
Unlocks OEM protected commands
!OEM
Modem state commands
!DIAG Sets diagnostic mode
!BOOTHOLD Resets modem and waits in boot loader
RF AT commands
!CHAN Sets RF band and channel
Proprietary and Confidential
Description
2130114