NEC mPD780851, Preliminary User'S Manual

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CHAPTER 6 16-BIT TIMER 0 TM0
Preliminary User’s Manual U14581EJ3V0UM00
6.3 16-Bit Timer 0 TM0 Configuration
16-bit timer 0 TM0 consists of the following hardware.
Table 6-2. 16-Bit Timer 0 TM0 Configuration
Item Configuration
Timer register 16 bits
×
1 (TM0)
Register Capture register: 16 bits
×
3 (CR00 to CR02)
Control register 16-bit timer mode control register (TMC0)
Capture pulse control register (CRC0)
Prescaler mode register (PRM0)
Port mode register 4 (PM4)
(1) 16-bit timer register 0 (TM0)
TM0 is a 16-bit read-only register that counts count pulses.
The counter is incremented in synchronization with the rising edge of an input clock. If the count value is read
during operation, the count value at that point is read. The value of the counter continues to be incremented
even while the count value is being read.
The count value is reset to 0000H in the following cases:
<1> RESET input
<2> Clear TMC02
(2) Capture register 00 (CR00)
The valid edge of the TI00 pin can be selected as the capture trigger. Setting of the TI00 valid edge is performed
with the prescaler mode register (PRM0). When the valid edge of the TI00 is detected, an interrupt request
(INTTM00) is generated.
CR00 is set with a 16-bit memory manipulation instruction.
RESET input makes CR00 to undefined.
(3) Capture register 01 (CR01)
The valid edge of the TI01 pin can be selected as the capture trigger. Setting of the TI01 valid edge is performed
with the prescaler mode register (PRM0). When the valid edge of the TI01 is detected, an interrupt request
(INTTM01) is generated.
CR01 is set with a 16-bit memory manipulation instruction.
RESET input makes CR01 to undefined.
(4) Capture register 02 (CR02)
The valid edge of the TI02 pin can be selected as the capture trigger. Setting of the TI02 valid edge is performed
with the prescaler mode register (PRM0). When the valid edge of the TI02 is detected, an interrupt request
(INTTM02) is generated.
CR02 is set with a 16-bit memory manipulation instruction.
RESET input makes CR02 to undefined.