Datasheet

Section 22 Flash Memory
R01UH0309EJ0500 Rev. 5.00 Page 1181 of 1408
Sep 24, 2012
H8S/2456, H8S/2456R, H8S/2454 Group
(f) Operating Clock Frequency Inquiry
The boot program will return the number of operating clock frequencies, and the maximum and
minimum values.
Command H'23
• Command, H'23, (1 byte): Inquiry regarding operating clock frequencies
Response H'33 Size Number of operating clock
frequencies
Minimum value of operating
clock frequency
Maximum value of operating clock
frequency
···
SUM
• Response, H'33, (1 byte): Response to operating clock frequency inquiry
• Size (1 byte): The number of bytes that represents the minimum values, maximum values, and
the number of frequencies.
• Number of operating clock frequencies (1 byte): The number of supported operating clock
frequency types
(e.g. when there are two operating clock frequency types, which are the main and peripheral
clocks, the number of types will be H'02.)
• Minimum value of operating clock frequency (2 bytes): The minimum value of the multiplied
or divided clock frequency.
The minimum and maximum values represent the values in MHz, valid to the hundredths place
of MHz, and multiplied by 100 (e.g. when the value is 64 MHz, it will be 6400 and H'1900).
• Maximum value (2 bytes): Maximum value of the multiplied or divided clock frequencies.
There are as many pairs of minimum and maximum values as there are operating clock
frequency.
• SUM (1 byte): Checksum