WCH BLE-SER User manual

BLE-SER1 http://wch.cn
BLE toUARTModule BLE-SER
Manual
Version:1D
http://wch.cn
1. Overview
The BLEtoUARTmodule(BLE-SER)isdeveloped based onCH9140,which supports BLE4.2. The baud
rateisup to1Mbps. The modulesupports Bluetooth LowEnergy(BLE)master-slave mode and slavemode,
and it supports automatic connection andbinding in master-slavemode.
Providing PC-side virtualserialdrivercan directlycallBluetoothinterface through the serialport,which is
compatiblewithserialdebug applications,soit can communicatewithUARTwithno secondary
developmentrequired, easilyimplementing the exemption ofwirepluggingandnotbeing limited bycable
distance.
BLE-SER appearance:
Some application block diagramsofCH9140:
Figure 1 Block diagramofserialcommunication between BLEhostand UARTdevice through CH9140
Figure 2 Block diagramofcommunication between MCUsorUARTdevicesthrough CH9140 inBLE
master-slave mode

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2. Features
ProvidesPC-side BLEvirtualserialport driver.
Compatible with existing serialsoftware and tools, withoutsecondarydevelopment.
Supports connection toBLEhostinWindows/Linux/Android/iOS and othersystems.
Supports BLEmaster-slave mode and slave mode.
Supports automatic connection and bindingin BLEmaster-slave mode.
Supports configure parameters byhardware.
Transmission distance:100 meters.
Adjustable 8 positionsofTXpower.
Power-offsleep currentis0.3uA.
Supports 3.3Vand 2.5Voperating voltages.
Asynchronousserialport default baud rate is115200bps.
Serialport supports MODEMsignals:RTSand CTS.
Serialport supports odd, even, no parity, space 0 and mark 1.
Supports obtain the chip supplyvoltage parameters.
3. Packagesize and pinsofBLE-SER-A
PinNo. PinName PinType Description
1 BLE_MODE I BLEmode setting, with built-in pull-up resistor
Lowlevel:Master-slavemode. High level: Slavemode
2 VCC P Powerinput
3 GND P Ground

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4 RELOAD
/LED I/O
Restore factorysetting inputpin (RELOAD)when powered on,
Restore the factorysettingsaftera lowlevelisdetected for2
secondscontinuously.
Chip statusindication signaloutputpin (LED)afterpowered on,
active low.
5 RTS# O MODEMoutputsignal, requestto send, active low.
6 CTS I MODEMinputsignal, clearto send, active low.
7 TXD O UARTtransmit pin
8 RXD I UARTreceive pin
Note:P:Power. I:Input. O:Output
4. Recommended bondingpadsize forBLE-SER-A
5. Layout
The upperpart ofthe moduleisthe on-boardantenna,and the layoutofantenna isrelated toqualityof
wireless communication. Good communication qualitycanensureastabledatatransmission rate. The
modulecan run separatelywithoutextraground plane, butwhen it isinstalled on the otherPCB,it shouldbe
noted:Antenna area mustbe farawayfromothermetalcomponents,and the distance mustbe greaterthan
20mm.Anyconductorclose to the antenna mayseriouslyaffectthe antenna radiation pattern.
The figurebelowshowsthe reference layoutofthe module. The first three casesarecorrect,aslong asthe
ground plane doesnotexceedthe ground plane edge ofthe module. The lastthree casesareincorrect.The
exampleon the left isincorrectbecausethereisaground plane underthe antenna,the middleexampleis
incorrectbecausethereisnotenough gap aroundthe antenna, and thelastexampleisincorrectbecause
batterymetalcasing isnotfarawayfromantenna area.
Symbol Value Unit
A 10.22
mm
B 10.6
C 1.02
D 0.8
E 1.27
F 0.74
G 1.7

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6. Functional description
6.1. Smartpairing
When theBLE-SER moduleisinmaster-slavemode, it can bepaired withthe designated CH9140/CH9143
withoutinputting MAC address through ATcommand.Aftersuccessfulpairing, the twowill establisha
binding relationship, andthere isno need tore-pair when connecting again.
Pairing procedure:
1)The CH9140 isin master-slavemode, and the CH9140/CH9143 isin slave mode ormaster-slavemode;
2)Both sidesneed to complete power-up within 3sto establish a pairing;
3)The indicatorLEDflashes3 timesand then keepson, indicating thatpairing issuccessful.
Ifthe userneedstore-establishthe pairing, repeatthepairing processagain.Thedifference isthatthe
indicatorLEDinstep 3will flashquickly.Inthiscase, thepairing can be re-established bypowering up the
chip ormodule.
6.2. Serialtransparenttransmissionfunction
AUARTisusedforserialtransparenttransmission. Thedefault setting is115200bit/sbaudrate,8databits,
1stop bit,noparityand enabled flowcontrol.The UARTreceiveand transmit buffers ofthe chipareeach
1Kbytes,and UARTwill performBLEtransmission inrealtimewhilereceiving data. BLEcommunication
rateisrelated toitsenvironment,soit isrecommended touseCTS/RTSflowcontroltopreventbuffer
overflowwhen BLEaverage RSSIisless than -70dBm.Butwhen thecommunicationqualityispoorand the
chipUARTreceiving speedisgreaterthan 2KB/s,it isrecommended touseCTS/RTSflowcontrolto
preventbufferoverflow.
6.3. LEDfunction
ListofLEDstatusdescription

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No. Status Description
1 once quicklyflashes3 timesafterpowered on currentlyin slave mode
2 twice quicklyflashes3 timesafterpowered on currentlyinmaster-slavemode
3 slowlyflashesat500msintervals currentlyin broadcaststatus
4 keepson currentlyin connection status
5 quicklyflashesin connectionstatus currentlyperforming data transmission
6 quicklyflashesin pairing process hasbeen paired with otherdevices, need
power-up again to complete pairing
Fordetails, please referto CH9140 datasheet.
7. Schematicdiagramforreference
3V3
GND
1K
R2
D1
LED0
3V3
RXD_CONNECT_MCU_TXD
TXD_CONNECT_MCU_RXD
GND
2
3 1
S1
Select 3formaster-slavemode
Select 1forslavemode
BLE_MODE
1
VCC
2
GND
3
RELOAD/LED
4
RXD 8
TXD 7
CTS 6
RTS# 5
U1
BLE-SER-A

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8. Reflowsolderingconditions
Moisture SensitivityLevel MSL3
Average slope rise rate (TLto TP) Maximum3℃/s
During warmup
Minimumtemperature(Tsmin) 150℃
Maximumtemperature(Tsmax) 200℃
Time (minimum –maximum)(ts) 60-180s
Tsmax –TLslope rise rate Maximum3℃/s
During hold
Temperature (TL) 217℃
Time (tL) 60-150s
Peak temperature (Tp) 260+0/-5℃
Time when actualpeak temperature iswithin 5℃(tp) 20-40s
Slope descentrate Maximum6℃/s
Time from25℃to peak temperature Maximum8 min