RX610 Group
26. ROM (Flash Memory for Code Storage)
R01UH0032EJ0120 Rev.1.20
Page 857 of 1006
Feb 20, 2013
(4) Using the Peripheral Clock Notification Command
The peripheral clock is used in programming and erasing the ROM, so the frequency of this clock has to be set in the
PCKAR. Frequencies in the range from 8 to 50 MHz are selectable. Do not set frequencies out of this range.
The peripheral clock notification command is used after the PCKAR setting has been made. In the first and second cycles
for the peripheral clock notification command, respectively, the values E9h and 03h are written to the address range for
programming and erasure of the ROM. Word-unit writing is used in the third to fifth cycles of the command.
Accordingly, make sure that the addresses used are aligned with four-byte boundaries. After 0F0Fh has been written
three times (as a word) to the address range for programming and erasure of the ROM, the process of the FCU setting the
frequency of the peripheral clock starts once the value D0h has been written as a byte in the sixth cycle. The FRDY bit in
FSTATR0 can be used to check whether or not the settings have been completed.
Addresses that can be used in the first to sixth cycles differ according to the settings of the FENTRY0 and FENTRY1*
bits in FENTRYR. Ensure that the addresses suit the settings of these bits. If issuing of the command is attempted with an
erroneous combination of the setting of the bits and specified addresses, the FCU will detect the error and enter the
command-blocked state (see section 26.8.2, Error Protection).
Furthermore, if the setting for the peripheral clock in use will not be changed from this setting after release from the reset
state, this setting is also valid for the next FCU command.
Note: * Cannot be used in a product whose ROM size is equal to or smaller than 1 Mbyte.