ML610Q409-NNNTBZ03A7 Rohm Semiconductor, ML610Q409-NNNTBZ03A7 Datasheet - Page 139

• Manufacturer Part Number: ML610Q409-NNNTBZ03A7
• Description: MCU 8BIT 16K FLASH 4CH 100-TQFP
• Manufacturer: Rohm Semiconductor
• Series: -r

Specifications of ML610Q409-NNNTBZ03A7

• Core Processor: nX-U8/100
• Core Size: 8-Bit
• Speed: 2MHz
• Connectivity: SSP, UART/USART
• Peripherals: LCD, Melody Driver, POR, PWM, WDT
• Number Of I /o: 22
• Program Memory Size: 16KB (8K x 16)
• Program Memory Type: FLASH
• Eeprom Size: -
• Ram Size: 1K x 8
• Voltage - Supply (vcc/vdd): 1.25 V ~ 3.6 V
• Data Converters: A/D 2x16b
• Oscillator Type: Internal
• Operating Temperature: -20°C ~ 70°C
• Package / Case: 100-TFQFP
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

9.3.2
The frequency measurement mode in 16-bit timer 2&3, is used to count the frequency of 500kHz RC oscillation clock
which typically has temperature variation and production tolerance.
Using the frequency measurement mode can make better accuracy for uart baud-rate clock or timer function.
(1) Reading the count data, calculating and setting it to uart communication baud-rate registers, can make more accurate
baud-rate clock.
(2) Reading the count data, calculating and setting it to a timer data register, can make more accurate timing in normal
timer mode.
Figure 9-3 shows the operation timing in frequency measurement mode.
(1) High-speed clock (HSCLK, HTBCLK) has to be in oscillating state by controlling with FCONn registers. And also
select 1/1 divide ratio of the high-speed time base counter by setting HTBDR (High-speed Time Base counter Divide
Register) register to 0FH.
(2) Reset both T2RUN bit (bit0 of TM2CON1 register) and T3RUN bit (bit0 of TM3CON1 register) to “0” to stop the
timer. And then, check both T2STAT bit (bit7 of TM2CON1 register) and T3STAT bit (bit7 of TM3CON1 register) are
“0” for making certain the timer stops.
(3) Set T23MFM bit (bit3 of TM2CON0 register) to “1” (Frequency measurement mode), set T23M16 bit (bit2 of
TM2CON0 register) to “1” (16bit mode) and set T2CS1-0 bits(bit1/0 of TM2CON0 register) to “01”(HTBCLK mode).
(4) Set “FFH” to both TM2D register and TM3D register.
(5) Clear both TM2C register and TM3C register to “00H”.
(6) Set T2RUN bit (bit0 of TM2CON1 register) to “1” to start counting the timer.
16-bit timer frequency measurement mode operation
T23MFM
T2STAT
T23M16
TM3INT
T2RUN
{TM3C,TM2C}
FFFF
437C
64Hz
0000
N1
(H)
(3)
Figure 9-3 Operation Timing in frequency measurement mode
(5)
(6)
(7)
9-21
437/32768S
ML610Q407/ML610Q408/ML610Q409 User's Manual
(8)
Chapter 9 Timer