BC04C

AT Commands

• Format for inquiry: Add ? after At commands, for example, AT+CHK?, AT+STOP?
• Format for setting: add parameter after AT commands, AT+BAUD1, AT+STOP1
• All the settings will store in the module and keep same after restart

	Function	Commands	Parameter	Example
1	General AT check	AT	-	-
2	Set Baud rate	AT+BAUD	1-1200; 2-2400; 3-4800; 4-9600; 5-19200; 6-38400; 7-57600; 8-115200	AT+BAUD1 return: OK+SetBaud:1200
3	Set check bit	AT+CHK	0: NO CRC, 1: ODD, 2:EVEN	-
4	Set Stop bit	AT+STP	1:1Stop, 2:2stop	-
5	Set UART	AT+UART[para1][para2][para3]	para1:baud rate, para2:CRC, para3:stop	-
	(Not available) Set module discoverable status	AT+ DISC	0:searchable and connectable, 1:only searchable, 2:connectable only	-
	(Not available) Set Pio0 function	AT+KEY	0: Cancel current status. 1: Cancel current status and restore factory setup.	-
	(Not available) Set PIO1 output status	AT+LED	0:Unconnected Output 500ms High 500ms Low, Connected output High. 1:Unconnected output Low, Connected output High.	-
6	Set module PIO Pins output status	AT+PIO	Length 10, every bit value is 1 or 0. 0: output low; 1:output high	AT+PIO? return OK+PIO0000000000; Setup PIO2 and PIO3output high and others output low: AT+PIO1100000000
6.1	Set PIO pins output high or low	AT+PIO[para1][para2]	Para1 is which PIO pin you want to Query/Set Value: 2,3,4,5,6,7,8,9,A,B. Para2 is Query or setup value. 0 is low and 1 is high	AT+PIO21
7	Set name	AT+NAME
8	Set name	AT+DEFAULT
9	Restart	AT+RESTART
10	Set Master and Slaver Role	AT+ROLE	M: Master S: Slaver	-
11	Set Pin Code	AT+PIN	Max length is 12, Allow A~Z	-
13	Clear pair data	AT+CLEAR		-
	(Not available) Scan slave device	AT+SCAN?	Notice: Work with “AT+IMME0” and “AT+ROLEM”	-
15	connect to device	AT+CONN		-
14	connect to last device	AT+CONLAST		-
	(Not available) Connect to a slave device MAC address	AT+LNK	Notice: Work with “AT+IMME0” and “AT+ROLEM”	-
21	Query Last Connected Device Address	AT+RADD?	-	-
19, 20	Query module address	AT+LADD? and AT+ADDR?	-	-
22	Query/Set Module work type	AT+IMME	0: When module is powered on, only respond the AT Command, don’t do anything. until AT + WORK is received 1: When power on, work immediately Notice: This command is only used for Master Role.	-
23	Start work	AT+WORK
24	Query/Set module connect remote device timeout value	AT+TCON	Para1 allowed value: 0000~9999 Unit is second. Default: 0000 Connect forever || -
25	check or set device type	AT+COD
26	Query/Set Module Work Mode	AT+TYPE	0:Transmission Mode; 1:Remote Control Mode; 2:PIO Collection Mode; Default: 0	-
	(Not available) Query/Set report PIO states string delay time(unit ms)	AT+TPIO	Para1 value is between 0000 and 9999 ms If value >0, when PIO states is changed, module will send PIO states string to remote device delay this value. Default: 0 send once	-
28	Switch Remote Control Mode to Transmission Mode(Only this time)	AT+START	-	-
29	Query/Set Buffer save parameter	AT+BUFF	0: Not save 1:Save Default: 0	-
	(Not available) Query/Set Module Notification	AT+NOTI	0: Don’t notify(default) 1:Notify when connected and disconnected	-

PIO0 (KEY) and PIO1 LED function

• PIO0 key: clear pairing info when not connected, disconnect, restart and enter into search mode when it is connected.
• RST button: Reset the module
• PIO1 LED: blink when not connected, and stay high when connected.

Working Mode

There are three types of working mode, see our videos to understand how it work firstly:

• Transmission mode: data can transfer via bluetooth remotely
• GPIO set mode (w/transmission mode): BC04C external GPIO can set remotely, first set working mode to 1 (AT+TYPE1) and use AT+PIO command to set GPIO.
• GPIO monitor mode (w/transmission mode): when external GPIO TTL status are changed, this info will send back, in a certain time frame, you need set AT+TYPE2, and AT+TPIO1000 for timing, 1000 means 1000 ms.

Demo code

#include <SoftwareSerial.h>
SoftwareSerial BTSerial(2, 3); // RX | TX
void setup()
{
  Serial.begin(9600);
  Serial.println("Enter AT commands:");
  BTSerial.begin(9600);  
}
void loop()
{

  if (BTSerial.available())
    Serial.write(BTSerial.read());
  if (Serial.available())
    BTSerial.write(Serial.read());
}

Note

• Use SSOM32 for testing (Un-tick "send new" option), the module do not need any simulate end after commands (\r\n).
• In arduino use first option on line ending
• When connected with other bluetooth devices, module will enter into data transmission mode, not command mode
• AT Command will not work on Data transmission mode (LED stay on)

First time usage and Control

• On the first time use, if you want to control the GPIOs, you should not connect the module with devices with BlueSPP first, otherwise when you connect to it, the module is working on data transfer mode.
• Disconnect any devices, and use a normal USB-TTL to setup working mode first, re-power the module and setup will be remembered inside, now you can connect and control.