Delta MMC120 - Manual (Page 46)

Flash Memory MMC 120 Motion Control Module
46 Delta Computer Systems, Inc. 360/254-8688
FLASH MEMORY
The MMC120 contains FLASH memory that has two user-accessible sections. Section 1 contains the
parameters and profiles for both axes. Section 2 contains the event step table for both axes. The two sections
have separate checksums; the checksums are tested on module power-up and on reset.
If the parameters initialize bit is off, check the parameter error bits, take the action described below to correct
the problem, then issue a 'P' command. Even if the parameter error bits are not set, you still must issue a 'P'
command to an axis before using it.
If the checksum for Section 1 is incorrect, the axis 1 parameter error bit will be turned on. If the checksum for
Section 2 is incorrect, the axis 2 parameter error bit will be turned on. If either of these bits is set, you must
update all the data for both axes in that section. For example, if the axis 2 parameter error bit is on, you must
update the event step table information for both axes.
To update the FLASH information, you must first download correct data to the MMC120 volatile memory.
Use the SET PARAMETERS command (type 3) to download the parameters, the SET PROFILES command
(type 2) to download the profiles, and the EVENT STEP TRANSFER command (type Extended E) to
download the event data. (See page 47 for command types.)
After the correct data has been downloaded to the MMC120's volatile memory, transfer it to the FLASH
memory with the 'U' command (55h). To transfer data to the parameter section (1), put a '1' in the
COMMAND VALUE field then issue a 'U' command. To transfer data to the event step table section (2), put
a '2' in the COMMAND VALUE field then issue a 'U' command. The 'U' command uses the Acknowledge bit
(9) of the Status word to report the result of the update. If the FLASH updated successfully, bit 9 of axis 1 is
toggled; if the update was unsuccessful, bit 9 of axis 2 is toggled.
The disadvantage to storing configuration data in the MMC120 is that when one module is replaced with
another, the stored data must be loaded into the new module. Because of this, all parameters, profiles, and
event step table data must be stored either in the ladder logic program or in a DCS120 file so they can be
transferred to an MMC120 when needed.