search

opencomputeproject / Time-Appliance-Project

Develop an end-to-end hypothetical reference model, network architectures, precision time tools, performance objectives and the methods to distribute, operate, monitor time synchronization within data center and much more...
MIT License
1.33k stars 101 forks source link

MAC_USB_PWR #36

Closed wisxxx closed 1 year ago

wisxxx commented 2 years ago

MAC_USB_PWR goes to connector P1B-B8 and thence to FPGA pin V8, IO_L14P_T2_SRCC_13, per the AC7100 schematics.

This is curious, since USB power is +5V and there is no +5 going to the FPGA. Also, what kind of IOH spec does that thing have?

ahmadexp commented 2 years ago

MAC_USB_PWR part of the USB bridge built on the MAC which is mainly used on the evaluation board of the MAC. In the Time Card we use the UART to communication with the MAC making the USB connection unnecessary.

wisxxx commented 2 years ago

Nonetheless, it appears that the power input to the MAC USB interface is incorrectly connected to an I/O pin on the FPGA, as shown on the currently available schematics. Can I assume that will be fixed on updated schematics?

AlphaBetaPhi commented 2 years ago

@wisxxx, yes this is fixed. For prototype and beta versions we allowed for numerous configurations of the MAC's and SOM modules for testing and evaluation. With upcoming releases, we have a condensed feature critical version with tested performance which does not include experimental options.

wisxxx commented 1 year ago

Still not fixed in "Prototype V7" schematics

Ref: file "Timingcard_PROJECT.pdf", in Time-Card/HW/ECAD/Prototype-V7/ECADv7.7z"

wisxxx commented 1 year ago

Fixed in production board (ref. schematic "R4006-G0001-03-SC-REV02.pdf").