Renesas rl78 Answering Machine User Manual


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RL78/G1A CHAPTER 6 TIMER ARRAY UNIT
R01UH0305EJ0200 Rev.2.00 206
Jul 04, 2013
6.3.4 Timer status register mn (TSRmn)
The TSRmn register indicates the overflow status of the counter of channel n.
The TSRmn register is valid only in the capture mode (MDmn3 to MDmn1 = 010B) and capture & one-count mode
(MDmn3 to MDmn1 = 110B). See Table 6-5 for the operation of the OVF bit in each operation mode and set/clear
conditions.
The TSRmn register can be read by a 16-bit memory manipulation instruction.
The lower 8 bits of the TSRmn register can be set with an 8-bit memory manipulation instruction with TSRmnL.
Reset signal generation clears this register to 0000H.
Figure 6-12. Format of Timer Status Register mn (TSRmn)
Address: F01A0H, F01A1H (TSR00) to F01AEH, F01AFH (TSR07) After reset: 0000H R
Symbol 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
TSRmn 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 OVF
OVF Counter overflow status of channel n
0 Overflow does not occur.
1 Overflow occurs.
When OVF = 1, this flag is cleared (OVF = 0) when the next value is captured without overflow.
Remark m: Unit number (m = 0), n: Channel number (n = 0 to 7)
Table 6-5. OVF Bit Operation and Set/Clear Conditions in Each Operation Mode
Timer operation mode OVF bit Set/clear conditions
clear When no overflow has occurred upon capturing Capture mode
Capture & one-count mode
set When an overflow has occurred upon capturing
clear Interval timer mode
Event counter mode
One-count mode
set
(Use prohibited)
Remark The OVF bit does not change immediately after the counter has overflowed, but changes upon the
subsequent capture.