3069RF-ZTAT Datasheet, PDF (468/1003 Pages) Renesas Technology Corp – RENESAS 16-BIT SINGLE-CHIP MICROCOMPUTER

Writing to RSTCSR: RSTCSR must be written by a word transfer instruction. It cannot be
written by byte transfer instructions. Figure 12.3 shows the format of data written to RSTCSR. To
write 0 in the WRST bit, the write data must have H'A5 in the upper byte and H'00 in the lower
byte. The data (H'00) in the lower byte is written to RSTCSR, clearing the WRST bit to 0.
Writing 0 in WRST bit
15
87
0
Address H'FFF8E*
H'A5
H'00
Note: * Lower 20 bits of the address in advanced mode.
Figure 12.3 Format of Data Written to RSTCSR
Reading TCNT, TCSR, and RSTCSR: These registers are read like other registers. Reading
TCNT, TCSR, and RSTCSR: These registers are read like other registers. Byte transfer
instructions can be used. The read addresses are H'FFF8C for TCSR, H'FFF8D for TCNT, and
H'FFF8F for RSTCSR, as listed in table 12.2.
Table 12.2 Read Addresses of TCNT, TCSR, and RSTCSR
Address*
Register
H'FFF8C
TCSR
H'FFF8D
TCNT
H'FFF8F
RSTCSR
Note: * Lower 20 bits of the address in advanced mode.
Rev. 5.0, 09/04, page 446 of 978