Maxim Integrated MAX31782 - Manual (Page 163)

MaximIntegrated 18-12
MAX31782 User’s Guide
Revision 0; 8/11
The JTAG bootloader also supports polling using the status bits as a method to determine when a word has success-
fully been written into flash . When sending the first two bytes of program data to load, the status bits should return as
11 to signify that the bootloader is valid . After sending the second byte, the bootloader begins writing this first word to
flash and is busy . If a third byte of data is written while the bootloader is busy programming the first word, the status
bits return as 10, which is loader busy . Upon receiving a status of 10, the third byte needs to be sent again until the
status bits return as 11, or loader valid . When this code is returned the third byte has been received and the fourth byte
can now be sent . If using the JTAG bootloader with a clock faster than 100kHz, this polling method should be used for
every byte that is transmit to the bootloader .
18.3.13Command11h—LoadData
This command writes (Length) bytes of data into the data SRAM starting at byte address (AddressH:AddressL) . The
MAX31782 uses a little-endian memory architecture where the least significant byte of each word is loaded first . For
example, if you load bytes (11h, 22h, 33h, 44h) starting at address 0000h, the first two words of memory space are
written to 2211h, 4433h . This command is password protected .
18.3.14Command20h—DumpCode
This command returns the contents of the program flash memory . The memory dump begins at byte address
AddrH:AddrL and contains LengthH:LengthL bytes . This command is password protected .
18.3.15Command21h—DumpData
This command returns the contents of the SRAM memory . The memory dump begins at byte address AddrH:AddrL and
contains LengthH:LengthL bytes . This command is password protected .
Byte1 Byte2 Byte3 Byte4
(Length)
Bytes Byte
Length+5 Byte
Length+6 Byte
Length+7
Command DataIn DataIn DataIn DataIn NOP Return DummyRX
Input 11h Length AddressL AddressH Data to load 00h 00h 00h
Output X X X X X X 3Eh X
Byte1 Byte2 Byte3 Byte4 Byte5 Byte5 Byte6
Length
Bytes Byte
Length+7 Byte
Length+8
Command DataIn DataIn DataIn DataIn DataIn NOP DataOut Return DummyRX
Input 20h 2 AddrL AddrH LengthL LengthH 00h 00h 00h 00h
Output X X X X X X X Memory 3Eh X
Byte1 Byte2 Byte3 Byte4 Byte5 Byte5 Byte6
Length
Bytes Byte
Length+7 Byte
Length+8
Command DataIn DataIn DataIn DataIn DataIn NOP DataOut Return DummyRX
Input 21h 2 AddrL AddrH LengthL LengthH 00h 00h 00h 00h
Output X X X X X X X Memory 3Eh X