Optional Upgrades

Optional Upgrades

Opening the F256K/F256K2/Wildbitsk2 case

To open the top half of the case, you will need a torx security size 8 screwdriver bit. To further disassemble the main board and take it out of the bottom half of the case, you will also need a Phillips size 1 bit and a torx security size 10 bit. You can check out the whole tear down operation in this video:

CR2032 coin cell battery for Real Time Clock

(F256K/F256K2/Wildbitsk2: requires the top half of the case being removed)

Install a 3V CR2032 battery to enable real time clock operations.

the Jr may possibly need another battery format

CPU integrated chip swap

W65C02S

W65C816S <---- the default choice choice for F256K/F256Jr. This comes soldered onboard for gen2 machines

For F256Jr/F256K only: 6809 as a FPGA on a mini DIP40 board. (the gen2 machines can act as a 6809 through a core binary file for the FPGA)

Feather Huzzah Wifi module (ESP8266)

Here's a full video guide on how to configure, solder and install an ESP8266 Feather Huzzah module from Adafruit into the F256K, could also apply to a F256Jr.

As for the F256Jr2 and F256K2, they have their own wifi solutions and would not benefit from this upgrade.

3.5 mm audio socket for stereo (year one production K and Jr units only)

If you have a Jr or K from 2023, chances are, your 3.5 mm audio socket is mono only by mistake. Here's a way to test this out.

Run the following BASIC program:

5 poke $D6A1,4: REM'set PSG_ST register to stereo mode'

10 poke $D600,$9C: REM'silence left channel'

20 poke $D600,$89: poke $D600, $3F:REM'send A2 to left channel'

30 poke $D610,$9C:REM'silence right channel'

40 poke $D610,$8A: poke $D610,$0A:rem'something else to right channel'

while capturing the audio in your favorite modern computer software (ie audacity). If you have stereo, you should clearly see a different tone in each left and right channels. If they're the same mixed tone on both channels, you have a mono socket.

It is possible to desolder the socket and replace a proper one, here are the tips from Stefany:

F256K - Your output will be Mono.

F256Jr - Your output will be working perfectly, but when you want to install an external audio connector on the front bezel, it is not going to work.

For the F256K, the line that could be cut are on the side of the board which means that one would need to desolder the connector to fix the issue.

the fix for f256k is either

1- remove, cut trace, reinstall

2- remove, reinstall the right jack connector with the right connector, the traces become irrelevent

The right part for the socket is: SJ1-3555NG