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V4 Assembly Notes

Giorgioggì edited this page Sep 23, 2023 · 4 revisions

Prerequisites

  • Read the V4 Configuration page, make sure you understand it and make your choices.

First Steps

  • If you decided for real ESD filters, install U91-U95, it's much easier if you do it first thing.
  • Add CN8, C100, C103, F100 (with 1.5A fuse), SW1, C101, C102, C104, C105, C106, C107, C109, R96.
  • Connect your power supply, take your multimeter and take some measurements inside the following rightmost points of the LF100 footprint:
    • DC mode between GND (black) and +5V (red): you must read a steady 5.0-5.2 V. If reading above that, change your power supply.
    • AC mode between +9VAC and -9VAC: you must read 9-12V. Readings above those shouldn't happen, anything below might still work.
  • Now you know your power supply is good, take it out and add LF100.
  • Add all components in the CLOCK GENERATOR box.
  • Connect your power supply, turn SW1 on, take your oscilloscope and check that you have a steady 17.7 MHz signal on TP1 (14.3 MHz for NTSC), at least 4 V peak-to-peak. You can use CT1 to tweak the frequency.

Main Assembly

  • Install U1, U2, U3/U4/U90 (according to chosen ROMs configuration), U5, U9, U10, U12, U13, U14, U15, U17, U18, U19 (needs programming), U26 (needs programming), U30.

  • Install ALL components that are NOT in a box.

  • Install components in the VIDEO OUTPUT AMPLIFIER box according to your chosen configuration.

  • Configure JP5/6/7/8 and JP13 according to chosen ROM configuration.

  • Make sure JP12 is closed.

    The board should start up to the BASIC screen at this point, showing 60671 bytes free, and most functionalities should be there, including floppy drives BUT NOT the Datassette.

RAM Expansion

  • Add U6, U25, U28 (needs programming), U29.
  • Use siz's RAM testing program to make sure that 256 kB are detected (512 kB in the future) and that no errors occur.

User Port

  • Add all components in the USER PORT box according to your chosen configuration

SID

  • U21 and U25 should have already been added
  • Add all components in the "SID" box (Again: BE CAREFUL!)
  • Use RV3 to tune the amount of SID sound that gets mixed with the TED sound to your liking.
  • If using an 8580, use RV4 to tune the volume of samples.

3rd joystick Port

  • After you have completed the SID section, add all components inside the JOY3 box.
  • Wire a male DB9 port to a female IDC connector using a 9/10-wire cable and plug it into CN14, taking care of correct orientation, and leave it hanging out the case through the tape or userport holes.
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