Hi,
I would like to understand the physical meaning (time unit) of the values in CSI-2 timing registers.
For instance, when our Deserializer operates at 800 Mbps, the read-out value of the automatically-set CSI0_THS_PREP[6:0] is:
0x06
On the other hand, according to Section 7.4.21 of DS90UB954-Q1 Datasheet, the value "recommended for 400 Mbps operation" of the lower 7 bits of the same register is:
0x03
According to the D-PHY standard (1.2), the valid range for T_HS-PREPARE should be something like:
[min 45ns - max 92.5ns] for 800 Mbps line-rate
[min 50ns - max 100ns] for 400 Mbps line-rate
My question:
How should I interpret those CSI-2 timing register values (0x06 and 0x03), so that I know for sure that the respective Deserializer CSI-2 timing settings (for 800 and 400 Mbps line-rate) comply with the D-PHY standard?
Specifically, can the time unit for those values be calculated as (8000 / lineRate) [ns] ?
e.g.
lineRate = 800 => Time unit = 8000/800 = 10 [ns]
and
lineRate = 400 => Time unit = 8000/400 = 20 [ns] ?
Thanks & best regards