HD6412240 RENESAS [Renesas Technology Corp], HD6412240 Datasheet - Page 437

• Manufacturer Part Number: HD6412240
• Description: Renesas 16-Bit Single-Chip Microcomputer H8S Family / H8S/2200 Series
• Manufacturer: RENESAS [Renesas Technology Corp]

Writing to RSTCSR
RSTCSR must be written to by word transfer instruction to address H'FFBE. It cannot be written
to with byte instructions.
Figure 11.3 shows the format of data written to RSTCSR. The method of writing 0 to the WOVF
bit differs from that for writing to the RSTE and RSTS bits.
To write 0 to the WOVF flag, the write data must have H'A5 in the upper byte and H'00 in the
lower byte. This clears the WOVF bit to 0, but has no effect on the RSTE and RSTS bits. To write
to the RSTE and RSTS bits, the upper byte must contain H'5A and the lower byte must contain the
write data. This writes the values in bits 6 and 5 of the lower byte into the RSTE and RSTS bits,
but has no effect on the WOVF flag.
Reading TCNT, TCSR, and RSTCSR
These registers are read in the same way as other registers. The read addresses are H'FFBC for
TCSR, H'FFBD for TCNT, and H'FFBF for RSTCSR.
Writing 0 to WOVF bit
Writing to RSTE and RSTS bits
Address: H'FFBE
Address: H'FFBE
Figure 11.3 Format of Data Written to RSTCSR
15
15
H'A5
H'5A
Rev.3.00 Mar. 26, 2007 Page 395 of 772
8 7
8 7
Section 11 Watchdog Timer
Write data
H'00
REJ09B0355-0300
0
0