Datasheet

Section 7 ROM
Rev.4.00 Nov. 02, 2005 Page 85 of 304
REJ09B0143-0400
Table 7.2 Boot Mode Operation
Communication Contents
Processing Contents
Host Operation
LSI Operation
Processing Contents
Continuously transmits data H'00
at specified bit rate.
Branches to boot program at reset-start.
Boot program initiation
H'00, H'00
. . .
H'00
H'00
H'55
Transmits data H'55 when data H'00
is received error-free.
H'XX
Transmits number of bytes (N) of
programming control program to be
transferred as 2-byte data
(low-order byte following high-order
byte)
Transmits 1-byte of programming
control program (repeated for N times)
H'AA reception
H'AA reception
Upper bytes, lower bytes
Echoback
Echoback
H'AA
H'AA
Branches to programming control program
transferred to on-chip RAM and starts
execution.
Transmits data H'AA to host when data H'55
is received.
Checks flash memory data, erases all flash
memory blocks in case of written data
existing, and transmits data H'AA to host.
(If erase could not be done, transmits data
H'FF to host and aborts operation.)
H'FF
Boot program
erase error
Item
Boot mode initiation
• Measures low-level period of receive data
H'00.
• Calculates bit rate and sets BRR in SCI3.
• Transmits data H'00 to host as adjustment
end indication.
H'55 reception.
Bit rate adjustment
Echobacks the 2-byte data
received to host.
Echobacks received data to host and also
transfers it to RAM.
(repeated for N times)
Transfer of number of bytes of programming control program
Flash memory erase