M38261ECFS datasheet(35/91 Pages) RENESAS

35 / 91 page

Rev.1.00

Sep 06, 2006

page 35 of 88

REJ03B0181-0100

3826 Group (One Time PROM version)

Fig. 33 Timing of serial I/O2 function

Synchronous clock

(Note 1)

Serial I/O2 output SOUT2

Serial I/O2 input SIN2

Serial I/O2 register

write signal

(Notes 2, 3)

Serial I/O2 interrupt request bit = “1”

1: When the internal clock is selected as the synchronous clock, the divide ratio can be selected by setting bits 0 to 2 of the

serial I/O2 control register.

2: When the internal clock is selected as the synchronous clock, the SOUT2 pin goes to high impedance after transfer

completion.

3: When the external clock is selected as the synchronous clock, the SOUT2 pin keeps D7 output level after transfer

completion. However, if synchronous clocks input are carried on, the transmit data will be output continuously from the

SOUT2 pin because shifts of serial I/O2 shift register is continued as long as synchronous clocks are input.

Notes

●Serial I/O2 Operating

The serial I/O2 counter is initialized to “7” by writing to the serial

I/O2 register.

After writing, whenever a synchronous clock changes from “H” to

“L”, data is output from the SOUT2 pin. Moreover, whenever a syn-

chronous clock changes from “L” to “H”, data is taken in from the

SIN2 pin, and 1 bit shift of the serial I/O2 register is carried out si-

multaneously.

When the internal clock is selected as a synchronous clock, it is

as follows if a synchronous clock is counted 8 times.

•Serial I/O2 counter = “0”

•Synchronous clock stops in “H” state

•Serial I/O2 interrupt request bit = “1”

The SOUT2 pin is in a high impedance state after transfer is com-

pleted.

When the external clock is selected as a synchronous clock, if a

synchronous clock is counted 8 times, the serial I/O2 interrupt re-

quest bit is set to “1”, and the SOUT2 pin holds the output level of

D7. However, if a synchronous clock continues being input, the

shift of the serial I/O2 register is continued and transmission data

continues being output from the SOUT2 pin.

M38261ECFS Folha de dados(PDF) 35 Page - Renesas Technology Corp

M38261ECFS Folha de dados(HTML) 35 Page - Renesas Technology Corp

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91

Folha de dados Download

Ligação URL