SH7708 datasheet(395/633 Pages) RENESAS

395 / 633 page

377

Figure 13.9 shows an example of communication among processors using the multiprocessor

format.

Receiving

station A

(ID = 01)

(ID = 02)

(ID = 03)

(ID = 04)

Receiving

station B

Receiving

station C

Serial communication circuit

H'01

H'AA

(MPB = 0)

(MPB = 1)

ID transmit cycle =

specifies receiving station

Serial

data

Transmitting

station

Receiving

station D

Data transmit cycle =

data transmission to

receiving station specified

by ID

MPB: Multiprocessor bit

Figure 13.9 Communication Among Processors Using Multiprocessor Format

(Example: Sending Data H'AA to Receiving Processor A)

Communication Formats: Four formats are available. Parity-bit settings are ignored when the

multiprocessor format is selected. For details see table 13.11.

Clock: See the description in the asynchronous mode section.

Transmitting Multiprocessor Serial Data: Figure 13.10 shows a sample flowchart for

transmitting multiprocessor serial data. The procedure for transmitting multiprocessor serial data

is:

1. SCI status check and transmit data write: Read the serial status register (SCSSR), check that

the TDRE bit is 1, then write transmit data in the transmit data register (SCTDR). Also set

MPBT (multiprocessor bit transfer) to 0 or 1 in SCSSR. Finally, clear TDRE to 0.

2. To continue transmitting serial data: Read the TDRE bit to check whether it is safe to write (if

it reads 1); if so, write data in SCTDR, then clear TDRE to 0.

3. To output a break at the end of serial transmission: Set the SPB0DT bit in the SCSPTR register

to 0, set SPB0IO to 1, then clear TE to 0 in SCSCR.

SH7708 Fiches technique(PDF) 395 Page - Renesas Technology Corp

SH7708 Fiches technique(HTML) 395 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

Fiches technique Télécharger

Lien URL