Tamarisk
®
320
Software ICD
13
Figure 1 - Download command sequence
2.6.1 Download from Thermal Imaging Module (TIM) to Connected Unit (CU)
A download from the TIM is initiated by the CU with the “Data Transfer Download Setup”
message (0x73). This messages has five, 16-bit parameters (10 bytes total). The parameters
identify the device; region, range, and size of the download (see Figure 1)
The TIM checks the size and region parameters and, if acceptable, responds with an ACK
(0x02).
The TIM then begins sending packets to the CU using “Data Transfer Download Packet”
messages (0x41). Each packet message carries a payload whose size is always an even
number of bytes. The payload packet contains a packet number (16-bits) and packet
payload bytes. Payload size has historically been 244 bytes. The packet number is a zero-
based, integer count packets. It is used to detect missing packets and to initiate retries. The
TIM continues to transmit packets until the entire object is transmitted.
At any time during the transmission, the CU may send a “Data Transfer Upload Retry”
message (0x46) to indicate an error. The retry contains one 16-bit parameter that is the
packet number of the last packet received in order. Upon receipt of this message, the TIM
will retransmit all packets following the packet number.
At any time, the CU may send a “Data Transfer Abort” message (0x43). Upon receipt of
this message, the TIM will terminate transmission of packets, reset its internal state
machines, and await a new setup message.
Following receipt of the last data packet, the CU will send a “Data Transfer Download
Complete” message (0x47). This message indicates that the entire object has been received
intact by the CU and that data transfer operations will cease.
2.6.1.1
Data Transfer Download Setup – 0x73
Description
: Setup a download from the TIM to the connected unit.
Command Format:
Table 11 – Data Transfer Download Setup Command Format
Byte
Value
Description
1
0x01
Start of message.
2
0x73
Data Transfer Download Setup Command ID.
3
0x0A
Parameters length.
4 to 7
unsigned integer
Transfer size in bytes.
8, 9
unsigned integer
0x0001
10, 11
unsigned integer
0x001A
12, 13
unsigned integer
0x0000.
14
Checksum
Frame check sequence.
