Specifications

AN93
62 Rev. 0.9
Figure 14. EEPROM Serial I/O Timing
3.3.3. Detailed EEPROM Examples
EEPROM Data is stored and read in hex ascii format in
eight address blocks beginning at a specified hex address.
For example, the AT:M0000,y0,y1,y2,y3,y4,y5,y6,y7
command writes the hex values y0…y7 at the hex
addresses from 0000 to 0007, respectively. The AT:E0000
command reads the hex values y0…y7 from the hex
addresses 0000 to 0007, respectively.
3.3.4. Boot Commands (custom defaults)
Commands to be executed upon boot-up are stored
between the heading “BOOT” and the first <CR><CR>
delimiter. The boot command has the following format:
BOOT<CR>
<commands><CR>
<commands><CR>
<CR>
The commands end with a <CR>, which, in combination
with the final<CR>, provides the <CR><CR> delimiter.
Boot commands must be the first entry in the EEPROM
and are used to set the modem up with custom defaults,
such as settings for specific countries, auto answer, or
other special settings upon power-up or after a
hardware or software reset. This saves the host
processor from reloading special configuration strings at
power up or after a reset and allows the modem to be
customized by programming the EEPROM or
substituting preprogrammed EEPROMs. If the BOOT
command is the final entry in the EEPROM, it must end
with an additional <CR> to provide the
<CR><CR><CR> delimiter indicating the end of the
EEPROM.
3.3.5. AT Command Macros (customized AT com-
mands)
Macros allow the creation of single custom AT
commands that execute combinations of default AT
commands including special register configurations. AT
command macros have the following format:
<command name><CR>
<commands><CR>
<commands><CR>
<CR>
Each AT Command Macro ends with a <CR><CR>. The
final entry in the EEPROM ends with an additional
<CR> to provide the <CR><CR><CR> delimiter
indicating the end of the EEPROM. AT command
macros can have a name consisting of any string of
characters but must be the only command on a line.
3.3.6. Firmware Upgrades
Firmware upgrades (“patches”) are typically executed
upon boot-up and stored between the heading, “BOOT”,
and the first <CR><CR> delimiter. A firmware upgrade
has the format: BOOT<firmware upgrade><CR>. The
firmware upgrade ends with a <CR>, which, in
combination with the final<CR>, provides the
<CR><CR> delimiter. Firmware upgrades can also be
stored as an AT command macro if there are cases
when using the firmware upgrade is optional.
ECLK
LSB
MSB
EISU
EOSU
EIH
EDH
ECSH
ECSW
EOZ
ECSS
EEPROM Data Format
EESD
EECS
8-bit instruction 16-bit address 8-bit data
EOH