Replica 1 plus Users Manual Step 15: Install the PS/2 keyboard connector. Use caution as the pins are fragile and the fit is very tight. The supplier recently changed brands and the connection is a little different. We have gone to great lengths to get the PS/2 holes corrected and matched up just right. Take your time and the connector will fit snug. Turn the replica 1 over and verify all pins have gone through the board. Solder the pins onto the replica 1. Figure 24: PS/2 keyboard connector Inspection of your work: Now that you have completed your soldering, take a few minutes and look over your work. Check for solder spots that might not be good connections to the posts.
Look for bridges where solder may have jumped over where it wasn’t supposed to go. Testing your replica 1: Before installing your IC’s, power up your replica 1. With your multi-meter, check the voltages 5V and GND. make sure your LED is lit properly. Test 3.3V and ground. Test pin 14 and pin 7 on the 74LS00 to make sure you are getting 5V. Check pin 8 and 16 on 74LS138 for 5V. Once you are satisfied that the power is being distributed correctly, power off the replica. Install the P8X32A-D40 and 24LC256 EEPROM. Attach an RCA cable to the replica 1 video port and attach it to your monitor or TV. Power up your replica 1 and see if you get a screen full of garbage.
If the video section is working properly, turn off the replica 1 and install the rest of the chips. Power up the replica 1 again, this time press ‘RESET’ button after a couple of seconds and see if the replica 1 resets. If the circuit is working properly, you will get a “ \ ” backslash followed by the cursor ‘ @ ’ moving to the next line. At this point you can power off the replica 1 once more and attach your keyboard. Power up the replica 1, reset the circuit and try out the keyboard. Congratulations, your replica 1 is now assembled and ready to use. Caution: Before plugging in the power supply, keyboard and video connector, thoroughly check over your work for errors.
Any parts that get accidentally damaged during the building process can be replaced at the owner’s expense. Contact Briel Computers for any replacement parts needed. The goal of Briel Computers is that ALL replica 1 kits get completed successfully. If you are having a problem, please feel free to ask for help. © Briel Computers 2014 page 19