D12320VF25V Datasheet, PDF (796/1146 Pages) Renesas Technology Corp – Old Company Name in Catalogs and Other Documents

Section 17 ROM
⎯ Division ratio: The inverse of the division ratio, i.e. a negative number (e.g. when the clock
is divided by two, the value of division ratio will be H'FE. H'FE = D'-2)
The number of multiplication ratios returned is the same as the number of multiplication ratios
and as many groups of data are returned as there are types.
• SUM (1 byte): Checksum
(6) 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
A number of operating
clock frequencies
The minimum value of
The maximum value of operating clock
operating clock frequency 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 types.
• A number of types (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 20.00 MHz, it will be D'2000 and
H'07D0.)
• Maximum value (2 bytes) : Maximum value among the multiplied or divided clock
frequencies.
There are as many pairs of minimum and maximum values as there are operating clock
frequencies.
• SUM (1 byte): Checksum
Rev.7.00 Feb. 14, 2007 page 762 of 1108
REJ09B0089-0700