r5f21346mnfp Renesas Electronics Corporation., r5f21346mnfp Datasheet - Page 272

• Manufacturer Part Number: r5f21346mnfp
• Description: Single-chip Mcus Incorporates The R8c Cpu Core
• Manufacturer: Renesas Electronics Corporation.

R8C/34M Group
R01UH0131EJ0100 Rev.1.00
Jun 21, 2011
18.5
Table 18.4
Note:
Count sources
Count operations
One-shot pulse
output time
Count start conditions • The TSTART bit in the TRBCR register is set to 1 (count starts) and the next
Count stop conditions • When reloading completes after timer RB underflows during primary period
Interrupt request
generation timing
TRBO pin function
INT0 pin functions
Read from timer
Write to timer
Selectable functions
In programmable one-shot generation mode, a one-shot pulse is output from the TRBO pin by a program or an
external trigger input (input to the INT0 pin) (refer to Table 18.4 Programmable One-Shot Generation Mode
Specifications). When a trigger is generated, the timer starts operating from the point only once for a given period
equal to the set value in the TRBPR register. The TRBSC register is not used in this mode.
Figure 18.4 shows an Operating Example of Programmable One-Shot Generation Mode.
1. The set value is reflected at the following one-shot pulse after writing to the TRBPR register.
Programmable One-shot Generation Mode
Item
Programmable One-Shot Generation Mode Specifications
f1, f2, f8, timer RA underflow
• Decrement the setting value in the TRBPR register
• When the timer underflows, it reloads the contents of the reload register before
• When the count stops, the timer reloads the contents of the reload register
(n+1)(m+1)/fi
fi: Count source frequency,
n: Setting value in TRBPRE register, m: Setting value in TRBPR register
• Set the TOSST bit in the TRBOCR register to 1 (one-shot starts)
• Input trigger to the INT0 pin
• When the TOSSP bit in the TRBOCR register is set to 1 (one-shot stops)
• When the TSTART bit in the TRBCR register is set to 0 (stops counting)
• When the TSTOP bit in the TRBCR register is set to 1 (forcibly stops counting)
In half a cycle of the count source, after the timer underflows (at the same time as
the TRBO output ends) [timer RB interrupt]
Pulse output
• When the INOSTG bit in the TRBIOC register is set to 0 (INT0 one-shot trigger
• When the INOSTG bit in the TRBIOC register is set to 1 (INT0 one-shot trigger
The count value can be read out by reading registers TRBPR and TRBPRE.
• When registers TRBPRE and TRBPR are written while the count is stopped,
• When registers TRBPRE and TRBPR are written during the count, values are
• Output level select function
• One-shot trigger select function
the count completes and the TOSSTF bit is set to 0 (one-shot stops).
before it stops.
trigger is generated
disabled): programmable I/O port or INT0 interrupt input
enabled): external trigger (INT0 interrupt input)
values are written to both the reload register and counter.
written to the reload register only (the data is transferred to the counter at the
following reload)
The output level of the one-shot pulse waveform is selected by the TOPL bit in
the TRBIOC register.
Refer to 18.5.3 One-Shot Trigger Selection .
(1)
.
Specification
Page 240 of 740
18. Timer RB