User's Manual

BlueFanBH661C,DualModeBluetoothModuleVer1.00July2016draft

✦ Character timeout

✦ Overrun error

✦ Framing error

TC35661 UART interface is used to transfer control command and data and is multiplexed with GPIO

pin. After to release reset state, TC35661 software sets UART interface to related GPIO pins.The

default bit rate depends on the selection ROM version. (e.g.

TC35661-503: 115,2kbps)

Flow Control Function

TC35661 UART interface uses flow control function by hardware signal, Transmit flow control (CTSX)

and receive flow control (RTSX). Above Figure shows signals input and

output direction .

CTSX input signal is used for UART transmitting. Low input indicates close of the preparation of the

other party to receive data and TC35661 executes UART transmitting data if there is data for

transmission. In case of input high level, TC35661 stops transmitting

by UART frame.

RTSX input signal is used for UART receiving. Low output indicates request data transmission to

UART transmitside device of the other party. TC35661 outputs Low level from RTSX when being able

to receive data and prepares to receive data.Response time of UART transmitting and receiving for

flow control signal depends on baud rate and internal process status of frame. It is from 1 frame to 4

frames.

Response time of UART transmitting and receiving for flow control signal depends on baud rate and

internal process status of frame. It is from 1 frame to 4 frame.

UART Baud Rate Setting

TC35661 UART interface has a programmable baud rate setting function. The UART baud rate can

be set according to the following equation. The baud rate generating clock frequency is set to either

39 MHz or 52 MHz. The over-sampling number is set to an integer that range from 1 to 65535.

UART Baud Rate = Baud rate generating clock frequency/(Over sampling number x dividing ratio)

The following table shows examples of UART baud rate setting. The maximum actual baud rate is

4,333,333 bps.

Target baud rate[bps] Actual baud rate[bps] clock(MHz)

Over-sampling

number

Dividing ratio Deviation[%]

115,200 116,071 39 12 28 0.7564

115,200 116,071 52 14 32 0.7564

921,600 928,571 39 14 3 0.7564

921,600 928,571 52 14 4 0.7564

1,843,200 1,875,143 52 14 2 0.7564

2,764,800 2,785,714 39 14 1 0.7564