Time Measurement Function - Renesas M16C FAMILY series Hardware Manual

M 1 6 C 2 / 8 G o r u p ( M 1 6 C

13.4 Time Measurement Function

In synchronization with an external trigger input, the value of the base timer is stored into the G1TMj
register (j=0 to 7). Table 13.5 shows specifications of the time measurement function. Table 13.6 shows
register settings associated with the time measurement function. Figures 13.19 and 13.20 display opera-
tional timing of the time measurement function. Figure 13.21 shows operational timing of the prescaler
function and the gate function.
Table 13.5 Time Measurement Function Specifications
Item
Measurement channel
Selecting trigger input polarity
Measurement start condition
Measurement stop condition
Time measurement timing
Interrupt request generation timing
(1)
INPC1j pin function
Selectable function
NOTES:
1. The INPC1 to INPC1
0
R e . v 2 0 . 0 J a . n 3 , 1 2 0 0 7
R E J 0 9 B 0 0 4 7 0 - 2 0 0
2 / , 8 M 1 6 C 2 / 8 ) B
Channels 0 to 7
Rising edge, falling edge, both edges of the INPC1j pin
The IFEj bit in the G1FE register should be set to "1" (channels j function
enabled) when the FSCj bit (j=0 to 7) in the G1FS register is set to "1" (time
measurement function selected).
The IFEj bit should be set to "0" (channel j function disabled)
•No prescaler : every time a trigger signal is applied
•Prescaler (for channel 6 and channel 7):
G1TPR
every
The G1IRi bit (i=0 to 7) in the interrupt request register (See Figure 13.9) is
set to "1" at time measurement timing
Trigger input pin
• Digital filter function
The digital filter samples a trigger input signal level every f
cycles and passes pulse signal matching trigger input signal level three
times
• Prescaler function (for channel 6 and channel 7)
Time measurement is executed every
trigger signal is applied
• Gate function (for channel 6 and channel 7)
After time measurement by the first trigger input, trigger input cannot be
accepted. However, while the GOC bit in the G1TMCRk register is set to
"1" (gate cleared by matching the base timer with the G1POp register (p=4
when k=6, p=5 when k=7)), trigger input can be accepted again by
matching the base timer value with the G1POp register setting
• Digital Debounce function (for channel7)
See section 13.6.2 and 17.6 for details
pins
7
page 152
f o 3 8 5
Specification
register value +1
times a trigger signal is applied
k (k=6,7)
G1TPRk register value +1
13. Timer S
(1)
, f or f
1 2 BT1
times a