HCS08 datasheet(204/316 Pages) NXP

204 / 316 page

Serial Communications Interface (S08SCIV4)

MC9S08SG8 MCU Series Data Sheet, Rev. 8

204

Freescale Semiconductor

14.2

The SCI has eight 8-bit registers to control baud rate, select SCI options, report SCI status, and for

transmit/receive data.

Refer to the direct-page register summary in the Memory chapter of this data sheet for the absolute address

assignments for all SCI registers. This section refers to registers and control bits only by their names. A

Freescale-provided equate or header file is used to translate these names into the appropriate absolute

addresses.

14.2.1

SCI Baud Rate Registers (SCIBDH, SCIBDL)

This pair of registers controls the prescale divisor for SCI baud rate generation. To update the 13-bit baud

rate setting [SBR12:SBR0], first write to SCIBDH to buffer the high half of the new value and then write

to SCIBDL. The working value in SCIBDH does not change until SCIBDL is written.

SCIBDL is reset to a non-zero value, so after reset the baud rate generator remains disabled until the first

time the receiver or transmitter is enabled (RE or TE bits in SCIC2 are written to 1).

321

LBKDIE

RXEDGIE

SBR12

SBR11

SBR10

SBR9

SBR8

Reset

000

= Unimplemented or Reserved

Figure 14-4. SCI Baud Rate Register (SCIBDH)

Table 14-1. SCIBDH Field Descriptions

Field

Description

LBKDIE

LIN Break Detect Interrupt Enable (for LBKDIF)

0 Hardware interrupts from LBKDIF disabled (use polling).

1 Hardware interrupt requested when LBKDIF flag is 1.

RXEDGIE

RxD Input Active Edge Interrupt Enable (for RXEDGIF)

0 Hardware interrupts from RXEDGIF disabled (use polling).

1 Hardware interrupt requested when RXEDGIF flag is 1.

4:0

SBR[12:8]

Baud Rate Modulo Divisor — The 13 bits in SBR[12:0] are referred to collectively as BR, and they set the

modulo divide rate for the SCI baud rate generator. When BR = 0, the SCI baud rate generator is disabled to

reduce supply current. When BR = 1 to 8191, the SCI baud rate = BUSCLK/(16

BR). See also BR bits in

Table 14-2.

HCS08 데이터시트(PDF) 204 Page - NXP Semiconductors

HCS08 데이터시트(HTML) 204 Page - NXP Semiconductors

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

데이터시트 다운로드

링크 URL