Data Format for HRB Trigger and Timing Control line, version 2.0
Previous version: 1.0
HRB Trigger and Timing Control on physical layer include 4 differential serial lines (LVDS standard):
- TRIGGER Line (TTB - Source)
- RESET Line (TTB - Source)
- CLOCK Line (TTB - Source)
- BUSY Line (TTB - Receiver)
CLOCK line serves for transmitting 125 MHz frequency signal. All other lines transmit data in 8B10B encoding, LSB first. In IDLE mode each serial line should transmit special word K28.5 for synchronization purpose.
TRIGGER line data format
8 |
7 |
6 |
5 |
4 |
3 |
2 |
1 |
trig fine time |
trig word |
||||||
- trig fine time - delay for trigger transmitting
- trig word:
- [4] - spill
- [3] - remote sync (verification that remote device is syncronized)
- [2] - rx sync (verification that host device is syncronized)
- [1] - trigger
RESET line - preliminary packet format
word # |
bits |
description |
0 |
7:4 |
Type |
3:0 |
Flags |
|
1 |
7:0 |
Sequence number |
2 |
7:0 |
Acknowledge number |
3 |
7:0 |
Payload |
4 |
7:0 |
|
5 |
7:0 |
|
6 |
7:0 |
|
7 |
7:0 |
|
8 |
7:0 |
|
9 |
7:0 |
|
10 |
7:0 |
|
11 |
7:0 |
CRC8 |
Available packet types:
- 0x01 - SYNC packet
- 0x02 - TRIG packet
- 0x03 - BUSY packet
- 0x04 - TIME packet
- 0x05 - ID packet
0x01 - NULL/SYNC packet
0x02 - TRIG/BUSY packet
0x03 - TIME packet
Flags:
- bit 3 - SYN
- bit 2 - ACK
- bit 1 - FIN
- bit 0 - RST
Flags works same as TCP ones.
Payload for different packet types
word # |
bits |
description |
||
SYNC/ID |
TRIG/BUSY |
TIME |
||
0 |
7:0 |
VME slot |
Trigger fine time |
Timestamp[7:0] |
1 |
7:0 |
TTB9V Port |
Trigger word |
Timestamp[15:8] |
2 |
7:0 |
TTB9V serial id [7:0] |
Timestamp[23:16] |
|
3 |
7:0 |
TTB9V serial id [15:8] |
Timestamp[31:24] |
|
4 |
7:0 |
TTB9V serial id [23:16] |
Timestamp[39:32] |
|
5 |
7:0 |
TTB9V serial id [31:24] |
Timestamp[47:40] |
|
6 |
7:0 |
TTB9V serial id [39:32] |
Timestamp[55:48] |
|
7 |
7:0 |
TTB9V serial id [47:40] |
Timestamp[63:56] |
|
- Trigger fine time - trigger transmission delay, 8ns step.
- Trigger word:
- [7:2] - reserved
- [1] - spill
- [0] - trigger
BUSY line data format
8 |
7 |
6 |
5 |
4 |
3 |
2 |
1 |
reserved |
remote sync |
rx sync |
busy |
||||
- [8:4] - reserved
- [3] - remote sync (verification that host device is syncronized)
- [2] - rx sync (verification that remote device is syncronized)
- [1] - busy