Maxim Integrated MAX31782 - Manual (Page 159)

MaximIntegrated 18-8
MAX31782 User’s Guide
Revision 0; 8/11
18.3BootloaderCommands
Commands for the MAX31782 loader are grouped into families . All bootloader commands begin with a single command
byte . The upper 4 bits of this command byte define the command family (from 0 to 15), while the lower 4 bits define the
specific command within that family . The loader command families are shown in
Table 18-5 .
Table18-5.CommandFamilies
All commands, except those in Family 0, are password protected . The password must first be matched before these
commands can be executed . This is done using the Password Match command, which clears the PWL bit if a match
is made .
Bootloader commands that fail for any reason set the bootloader status byte to an error code value describing the rea-
son for the failure . This status byte can be read by means of the Get Status command .
For proper bootloader operation, all bytes of data listed for the command must be written or read from the bootloader .
This includes the Return byte, and for the I
2 C bootloader, the Dummy RX byte . If all bytes are not read, the bootloader
remains in an unknown state even after a new command is sent to the bootloader .
Following are descriptions of the bootloader commands that are available for use by the MAX31782 bootloader .
18.3.1Command00h—NoOperation
This is a No Operation command . This command can be sent at any time without the bootloader taking action . This
command is not password protected .
18.3.2Command01h—ExitLoader
This command causes the bootloader to exit . When exiting, the bootloader clears the JTAG_SPE and I2C_SPE bits and
then performs an internal reset of the device . Following the reset, code execution jumps to the beginning of application
code at address 0000h . This command is not password protected .
COMMANDFAMILY FAMILYDESCRIPTION
0 Required
1 Load
2 Dump
3 CRC
4 Verify
5 Load and Verify
E Fixed Length Erase
Byte1
Command
Input 00h
Output X
Byte1
Command
Input 01h
Output X