Test and measurement hardware abstraction library and protocol decodes. This is the library only. Most users should use scopehal-apps.
BSD 3-Clause "New" or "Revised" License
216
stars
97
forks
source link
USB2PMADecoder: Use different threshold for Differential and Single Ended #769
Closed
smunaut closed 1 year ago
The threshold to use to see if we have a valid differential signals (DP - DN) is different from the one to use to see if we're in SE00 or SE11.
For LS/FS USB 2.0 - 7.1.71 - Table 7-2 States that 200 mV differential is enough and that SE1 requires both lines to be above Vil
For HS USB 2.0 - 7.1.7.2 - Table 7-3 States that 150 mV differential is enough
USB 2.0 - 7.3.2 - Tables 7-7 Gives Vil = 0.8V