UPD78F0988AGC-8BS Renesas Electronics America, UPD78F0988AGC-8BS Datasheet - Page 119

• Manufacturer Part Number: UPD78F0988AGC-8BS
• Manufacturer: Renesas Electronics America

Specifications of UPD78F0988AGC-8BS

• Lead Free Status / Rohs Status: Supplier Unconfirmed

(4) Prescaler mode register 00, 01 (PRM00, PRM01)
PRM00
Notes 1. Expanded-specification products only
This register is used to set the 16-bit timer counter 00, 01 (TM00, TM01) count clock and TI000, TI001 input valid
edges.
PRM00 and PRM01 are set by an 8-bit memory manipulation instruction.
RESET input sets PRM00 and PRM01 to 00H.
Cautions 1. If the valid edge of TI000 is set for the count clock, do not set it for the clear & start mode
Remarks 1. f
Symbol
2. The external clock requires a pulse longer than two internal clocks (f
ES101 ES100
ES001 ES000
PRM001 PRM000
ES101
0
0
1
1
0
0
1
1
0
0
1
1
2. TI000, TI010: Input pins of 16-bit timer/event counter 00
2. PRM00 should be set only after timer operation has been stopped.
3. If the TI000 pin or TI010 pin is high level immediately after system reset, and the rising edge
7
or the capture trigger. Also, the P54/TI000/TO00/INTP4 pin cannot be used as a timer output
(TO00).
or both edges are specified as the valid edge of TI000 pin or TI010 pin thus enabling
operation of 16-bit timer counter 00 (TM00), the rising edge will be detected immediately.
Care is therefore needed if the TI000 pin or TI010 pin is pulled up. When operation is enabled
again after being stopped, the rising edge cannot be detected.
X
: System clock oscillation frequency
ES100
0
1
0
1
0
1
0
1
0
1
0
1
6
Rising edge
Both falling and rising edges
Rising edge
Both falling and rising edges
fx/2
TI000 valid edge
Falling edge
Setting prohibited
Falling edge
Setting prohibited
fx
fx/2
Figure 6-9. Format of Prescaler Mode Register 00
ES001
2
5
5
3 MHz
12 MHz
375 kHz
CHAPTER 6 16-BIT TIMER/EVENT COUNTER
At f
ES000
TI010 valid edge selection
TI000 valid edge selection
X
4
Note 2
= 12 MHz
Count clock selection
User’s Manual U13029EJ7V1UD
3
0
Note 1
2
0
8.38 MHz
2.09 MHz
262 kHz
At f
PRM001 PRM000
X
= 8.38 MHz
1
0
Address
FF61H
X
/2
4
).
After reset
00H
R/W
R/W
117