// allocate two bytes for to hold a 10-bit analog reading
uint8_t payload[7];
int value1 = 100; // data to be sent

payload[0] = value1 >> 8 & 0xff; // payload[0] = MSB.
payload[1] = value1 & 0xff; // 0xff = 1111 1111, i.e.

Tx16Request tx_5001 = Tx16Request(0x5001, payload, sizeof(payload));
xbee.send(tx_5001);

uint8_t payload[7];
int value1 = 100; // data to be sent

payload[0] = value1 >> 8 & 0xff; // payload[0] = MSB.
payload[1] = value1 & 0xff; // 0xff = 1111 1111, i.e.