Section 12 16-Bit Free-Running Timer (FRT)
Rev. 2.00 Mar 09, 2006 page 528 of 906
REJ09B0292-0200
Bit 0—Output Level B (OLVLB): Selects the level output to the output compare B output pin
upon compare match B (signal indicating match of FRC and OCRB).
Bit 0: OLVLB
Description
0
0 output on compare match B
(Initial value)
1
1 output on compare match B
12.3
CPU Interface
FRC, OCRA, OCRB, and FICR are 16-bit registers. The data bus width between the CPU and
FRT, however, is only 8 bits. Access of these three types of registers from the CPU therefore
needs to be performed via an 8-bit temporary register called TEMP.
The following describes how these registers are read from and written to:
•
Writing to 16-bit Registers
The upper byte is written, which results in the upper byte of data being stored in TEMP. The
lower byte is then written, which results in 16 bits of data being written to the register when
combined with the upper byte value in TEMP.
•
Reading from 16-bit Registers
The upper byte of data is read, which results in the upper byte value being transferred to the
CPU. The lower byte value is transferred to TEMP. The lower byte is then read, which results
in the lower byte value in TEMP being sent to the CPU.
When registers of these three types are accessed, two byte accesses should always be performed,
first to the upper byte, then the lower byte. If only the upper byte or lower byte is accessed, the
data will not be transferred properly.
Figure 12.2 and 12.3 show the flow of data when FRC is accessed. Other registers function in the
same way. When reading OCRA and OCRB, however, both upper and lower-byte data is
transferred directly to the CPU without passing through TEMP.
Summary of Contents for SH7616
Page 10: ...Rev 2 00 Mar 09 2006 page x of xxvi ...
Page 132: ...Section 2 CPU Rev 2 00 Mar 09 2006 page 106 of 906 REJ09B0292 0200 ...
Page 568: ...Section 12 16 Bit Free Running Timer FRT Rev 2 00 Mar 09 2006 page 542 of 906 REJ09B0292 0200 ...
Page 582: ...Section 13 Watchdog Timer WDT Rev 2 00 Mar 09 2006 page 556 of 906 REJ09B0292 0200 ...
Page 706: ...Section 16 Serial I O SIO Rev 2 00 Mar 09 2006 page 680 of 906 REJ09B0292 0200 ...
Page 820: ...Section 19 Pin Function Controller PFC Rev 2 00 Mar 09 2006 page 794 of 906 REJ09B0292 0200 ...
Page 932: ...Appendix D Package Dimensions Rev 2 00 Mar 09 2006 page 906 of 906 REJ09B0292 0200 ...
Page 935: ...SH7616 Hardware Manual ...