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3 command 02h—master erase, 4 command 03h—password match, 5 command 04h—get status – Maxim Integrated MAX31782 User Manual

Page 160: Table 18-6 . bootloader status flags -9, 3command02h—mastererase, 4command03h—passwordmatch, 5command04h—getstatus, Table18-6.bootloaderstatusflags

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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 .