33
Chapter 3 - AT Commands
Table 3-2. Where the Modem Reads Configuration Parameters
Power-On
Previous Command AT&F and ATZ
AT&W1 (default) ROM ROM
AT&W0 ROM NVRAM
AT&F8&W0 ROM NVRAM
AT&F9&W0 NVRAM NVRAM
Z Reset Modem
The Z command resets the modem to its default configuration and clears the command
buffer. The result is the same as turning the modem off and on. When you type ATZ, the
state of the &W command determines where the default values originate. &W0 defaults
come from the customized configuration in NVRAM, and &W1 defaults come from the
factory default configuration in ROM. Because Z clears the command buffer, it must be the
last command in a command string; normally it is issued by itself: ATZ.
Note that the Z reset command operates differently from the &F reset command. See Table
3-2.