Jerry's IAP sending function [section]

extern int user_iap_send_data(u8 rfcomm_cid, u8 *buf, u16 len); If it is an application that supports multiple mobile phone connections, the value of the parameter rfcomm_cid needs to use the channel value of the callback function __iap2_data_deal. If you only support a mobile phone connection, you can directly pass parameter 0, and the address of the current connection will be found to connect. If not, the packet will be lost directly.