DF61657CN35FTV Renesas Electronics America, DF61657CN35FTV Datasheet - Page 636

• Manufacturer Part Number: DF61657CN35FTV
• Description: IC H8SX/1657 MCU FLASH 120TQFP
• Manufacturer: Renesas Electronics America
• Series: H8® H8SX/1600r

Specifications of DF61657CN35FTV

• Core Processor: H8SX
• Core Size: 32-Bit
• Speed: 35MHz
• Connectivity: SCI, SmartCard
• Peripherals: DMA, PWM, WDT
• Number Of I /o: 82
• Program Memory Size: 768KB (768K x 8)
• Program Memory Type: FLASH
• Ram Size: 24K x 8
• Voltage - Supply (vcc/vdd): 3 V ~ 3.6 V
• Data Converters: A/D 8x10b; D/A 2x8b
• Oscillator Type: Internal
• Operating Temperature: -20°C ~ 75°C
• Package / Case: 120-TQFP, 120-VQFP
• For Use With: 3DK1657 - DEV EVAL KIT FOR H8SX/1657
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -

Section 14 Serial Communication Interface (SCI)
14.7.4
Only the internal clock generated by the on-chip baud rate generator can be used as a transfer
clock in smart card interface mode. In this mode, the SCI can operate on a basic clock with a
frequency of 32, 64, 372, or 256 times the bit rate according to the BCP1 and BCP0 bit settings
(the frequency is always 16 times the bit rate in normal asynchronous mode). At reception, the
falling edge of the start bit is sampled using the basic clock in order to perform internal
synchronization. Receive data is sampled on the 16th, 32nd, 186th and 128th rising edges of the
basic clock so that it can be latched at the middle of each bit as shown in figure 14.25. The
reception margin here is determined by the following formula.
Assuming values of F = 0, D = 0.5, and N = 372 in the above formula, the reception margin is
determined by the formula below.
Rev. 2.00 Jun. 28, 2007 Page 610 of 864
REJ09B0341-0200
Internal
basic clock
Receive data
(RxD)
Synchronization
sampling timing
Data sampling
timing
Figure 14.25 Receive Data Sampling Timing in Smart Card Interface Mode
M: Reception margin (%)
N: Ratio of bit rate to clock (N = 32, 64, 372, 256)
D: Duty cycle of clock (D = 0 to 1.0)
L: Frame length (L = 10)
F: Absolute value of clock frequency deviation
M = ( 0.5 –
M = | (0.5 –
Receive Data Sampling Timing and Reception Margin
(When Clock Frequency is 372 Times the Bit Rate)
2 × 372
2N
1
0
186 clock
1
cycles
) – (L – 0.5) F –
372 clock cycles
) × 100% = 49.866%
185
Start bit
371
| D – 0.5 |
0
N
D0
(1 + F ) | × 100%
185
371 0
D1