Milkymist One RC3 Known Issues

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Here is the known issues found during debugging and testing RC3


[edit] from contributors

  • From Joerg & Werner [4], for Adam's review
1. Short L3 to fix audio problem
2. R11 should be 0R otherwise we loose stereo separation for the CD input on the expansion header
3. joerg would put ~50 pF in parallel to R23 and R24, to filter HF and to absorb ESD (there's no ESD protection on line in)

[edit] Major errors

[edit] the intermittent loss of video input

  • the intermittent loss of video input, replace L19 with short connection by soldering on run3 boards. In RC4, will have no this part[5] with routing in wire to connect two planes under video decoder, see page 95, figure 41.

[edit] darn of never booted up

  • darn of never booted up about solutions from reset IC and diode:

[edit] Proposed pre-rc4 reset schematic

  • Proposed pre-rc4 schematic for design verification on RESET to solve nor-corruption.
  • L1's footprint needs to be smaller and same as 0402.

[edit] Minor errors and improvements

  • Downsize the pin number of J3 to two 1x3pins 2.54mm pitch header footprints of Jx and Jy and DNP in rc4 and close to audio codec. See J3 redesign for rc4 on list.
  • to remove the need for the metal sheet, Joerg suggested using 5mm wide endless aluminium sticky tape and attach two stripes across the diagonals of the bottom PCB side. He would connect them to the spacer only on one side, in the middle crossing they would ideally be isolated by the glue. [6]
  • We are thinking about replacing the VGA connector with a DVI-I connector (single-link), for some notes see mail and irc log, direct connection.
  • Werner propoased that adding another same pins of J21 to make a "U"-shaped and need to fully specify the expansion system and decided to use like female receptacle socket, so that DIY can build small circuit to plug on it.

[edit] switch to ADV7181C

1. Remove L14 ~ L16, C202 ~ C207 entirely
2. Short L14 ~ L16
3. replace U21 with an ADV7181CBSTZ

[edit] add USB Power Switch

  • usb power switch
demand = patch wants to use feature X but nothing seems to be connected
activity = an aperiodic flash every now and then
problems = maybe periodically blink

[edit] R4 draft feedback

Items below have not been finished yet, see latest R4 draft

1. establish software on m1 to be in full control and awareness of what is going on, including cable insertion/removal, so review all I/O's hardware circuit.

a.) DC power in: yes, ref. (no real 'detection' because DC is the only power source, this only refers to the power LED and ability to override the power LED)
b.) auido line-in/out: yes, ref.
c.) DMX TX/RX: no
d.) MIDI TX/RX: no for TX, ref.; but propably be s/w for RX, ref.
e.) video-in R, G, B RCA: no
f.) ethernet: no need
g.) DVI-I: yes, ref.
h.) usb ports: no need

2. DVI-I +5V DDC precaution/protection on short case, ref. 1, ref. 2

3. keep only one middle button by using state machine for the button behaviour.

4. J21/J22 connector size with way to keying. Joerg suggested to cut pin 4 of J21 and pin 1 of J22. With this kind of keying, ref.

5. add a mechanism way to strengthen around J21 while user using extension board, ref.

[edit] Links

Milkymist One Schematic Change History

Milkymist One RC2 Known Issues

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