H8S2144B Datasheet, PDF (400/546 Pages) Renesas Technology Corp – Renesas 16-Bit Single-Chip Microcomputer H8S Family/H8S/2100 Series

Section 16 ROM
Table 16.5 Boot Mode Operation
Host Operation
Processing Contents
Communications Contents
LSI Operation
Processing Contents
Branches to boot program at reset-start.
Boot program start
Continuously transmits data H'00
at specified bit rate.
H'00, H'00 ^{. . .} H'00
Transmits data H'55 when data H'00
H'00
is received error-free.
H'55
Receives data H'AA.
H'AA
Transmits number of bytes (N) of
programming control program to be
transferred as 2-byte data (low-order byte
following high-order byte).
High-order byte and
low-order byte
Echoback
Transmits 1-byte of programming control
program (repeated for N times).
H'XX
Echoback
• Measures low-level period of receive data H'00.
• Calculates bit rate and sets it in BRR of SCI_1.
• Transmits data H'00 to host as adjustment end
indication.
After receiving data H'55, transmits data
H'AA to host.
Echobacks the 2-byte data received to host.
Echobacks received data to host and also
transfers it to RAM (repeated for N times).
Boot program
erase error
Receives data H'AA.
H'FF
H'AA
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.)
Branches to programming control program
transferred to on-chip RAM and starts
execution.
Rev. 1.00 Jun.24, 2005 Page 368 of 510
REJ09B0241-0100