SH7721 datasheet(679/1524 Pages) RENESAS

679 / 1524 page

Section 18

Serial Communication Interface with FIFO (SCIF)

Rev. 3.00 Jan. 18, 2008 Page 617 of 1458

REJ09B0033-0300

(4)

Transmitting and Receiving Data (Serial data transmission)

Figure 18.3 shows a sample serial transmission flowchart. After SCIF transmission is enabled, use

the following procedure to perform serial data transmission.

Start transmission

Read TDFE bit in SCSSR

TEND= 1?

Read TEND bit in SCSSR2

Clear TE bit in SCSCR2 to 0

Set SCPDR2 and SCPCR2

Yes

TDFE= 1?

All data transmitted?

Yes

Break output?

Yes

Write transmit data (16 - transmit

trigger set number) to SCFTDR,

read 1 from TDFE bit and TEND flag

in SCSSR, then clear to 0

End of transmission

(1) SCIF status check and transmit data write:

Read serial status register (SCSSR) and

check that the TDFE flag is set to 1, then

write transmit data to the transmit FIFO

data register (SCFTDR), read 1 from the

TDFE and TEND flags, then clear these

flags to 0.

The number of transmit data bytes that can

be written is 64 - (transmit trigger set

number).

(2) Serial transmission continuation procedure:

To continue serial transmission, read 1 from

the TDFE flag to confirm that writing is

possible, then write data to SCFTDR2, and

then clear the TDFE flag to 0.

(3) Break output at the end of serial

transmission:

To output a break in serial transmission, set

the port SC data register (SCPDR) and port

SC control register (SCPCR), then clear the

TE bit to 0 in the serial control register

(SCSCR).

In steps 1 and 2, it is possible to ascertain

the number of data bytes that can be

written from the number of transmit data

bytes in SCFTDR indicated by the upper 8

bits of the FIFO data count set register 2

(SCFDR).

(1)

(2)

(3)

Figure 18.3

Sample Serial Transmission Flowchart

SH7721 Datasheet(PDF) 679 Page - Renesas Technology Corp

SH7721 Datasheet(HTML) 679 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 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL