Maxim Integrated MAX31782, User Manual

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MaximIntegrated 18-9
MAX31782 User’s Guide
Revision 0; 8/11
18.3.3Command02h—MasterErase
This command erases (sets to FFFFh) all words in the program flash memory and writes all words in the data SRAM
to zero . This command is not password protected . After this command completes, the password lock bit is automati-
cally cleared, allowing access to all bootloader commands . This command requires approximately 40 ms to complete .
Polling for a return value of 3Eh can be performed during this execution time to determine when the master erase has
completed .
18.3.4Command03h—PasswordMatch
This command accepts a 32-byte password value, which is matched against the password in program memory from
byte address 0020h through 003Fh . If the entered value matches the password in program memory, the password lock
bit is cleared . This command is not password protected .
18.3.5Command04h—GetStatus
The Status Flags and Status Code returned by the Get Status command are defined in Table 18-6 and Table 18-7 . This
command is not password protected . The Status Codes are set whenever an error condition occurs and only reflect the
last error . The Status Codes are cleared:
• When the bootloader is initially entered .
• At the start of execution of all commands except Familiy 0 commands .
• At the start of execution of the Family 0 Master Erase and Set Access Mode commands .
Table18-6.BootloaderStatusFlags
Byte1 Byte2 Byte3 Byte4
Command NOP Return DummyRX
Input 02h 00h 00h 00h
Output
X X 3Eh X
Byte1 Bytes2to33 Byte34 Byte35 Byte36
Command DataIn NOP Return DummyRX
Input 03h 32-Byte Password 00h 00h 00h
Output X X X 3Eh X
Byte1 Byte2 Byte3 Byte4 Byte5 Byte6
Command NOP DataOut DataOut Return DummyRX
Input
04h 00h 00h 00h 00h 00h
Output X X Flags Status Code 3Eh X
FLAGBIT MEANING
8:3 Reserved.
2
Word/ByteModeSupported.
0 – The bootloader supports byte mode only .
1 – The bootloader supports word mode as well as byte mode .
(Note:theMAX31782supportsbytemodeonly)
1
Word/ByteMode.
0 – The bootloader is currently in byte mode for memory reads/writes .
1 – The bootloader is currently in word mode for memory reads/writes .
(Note:theMAX31782supportsbytemodeonly)
0
PasswordLock.
This bit will match the SC .PWL bit .
0 – The password is unlocked or had a default value; password-protected commands may be used .
1 – The password is locked . Password-protected commands may not be used .