TELINK SEMICONDUCTOR TLSR8232, Application Note

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Telink TLSR8232 BLE SDK Developer Handbook
AN-19112700-E1 97 Ver.1.0.0
u8 att ; //opcode
u8 hl ; //low byte of Atthandle
u8 hh ; //high byte of Atthandle
u8 dat [20];
} rf_packet_att_data_t ;
“p” points to “dma_len”, valid length of data is l2cap minus 3, and the first valid data is
pw->dat[0].
int my_WriteCallback ( void *p)
{
rf_packet_att_data_t *pw = ( rf_packet_att_data_t *)p;
int len = pw-> l2cap - 3;
//add your code
//valid data is pw->dat[0] ~ pw->dat[len-1]
return 1;
}
The structure “rf_packet_att_data_t” above is available in “stack/ble/ble_common.h”.
3.4.2.6 Callback Function r
The callback function r is a read function, its prototype is:
typedef int (*att_readwrite_callback_t)(void* p);
Users must follow the format above to define callback read function. The callback
function r is also optional, i.e. for an Attribute, user can select whether to set the callback
read function as needed (null pointer 0 indicates not setting callback read function).
The trigger condition for callback function r is: When Slave receives any Attribute PDU
with Attribute Opcode as shown below, Slave will check whether the callback function r is
set.
1) opcode = 0x0A, Read Request, see Core_v5.0 .
2) opcode = 0x0C, Read Blob Request, see Core_v5.0 .
After Slave receives a read command above,
1) If the callback read function is set, Slave will execute this function, and determine
whether to respond with “Read Response/Read Blob Response” according to the
return value of this function.
a) If the
return value is 1, Slave won’t respond with “Read Response/Read Blob
Response
” to Master.
b) If the return value is
not 1, Slave will automatically read “attrLen” bytes of data
from the area pointed by the “pAttrValue”, and the data will be responded to
Master via “Read Response/Read Blob Response”.