Datasheet
Section 21 Flash Memory 
Page 1110 of 1384    R01UH0310EJ0500 Rev. 5.00 
 Sep 25, 2012 
H8S/2426, H8S/2426R, H8S/2424 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 










