tach the power cable. Wait a few moments then release both keys. You should see the following screen:  ``` ZX Spectrum Next Configuration Anti-Brick Board Id ZX Next Issue 4 Slot 01 Version 3.02.00 Do you want to upgrade? (y/n)y Verifying checksum \ ``` *Fig. 51 – AB Core update screen* If the display is blank, press **F3** on the keyboard. Note that due to AB core using the **NMI** and **Drive** buttons you cannot press **F3** using the **NMI + 3** shortcut so you must have a PS/2 keyboard for that. The display could be blank because the AB core works at 60 Hz in VGA mode only so if your display cannot "lock" onto that mode and you have no PS/2 keyboard to attach, you will need to do a so-called "blind update". You can still press **y** and more than likely the update will finish however if you have no display, the preferred method of performing said update is by pressing the **NMI** button once which in AB core update is a shortcut for **y** while the **Drive** button is a shortcut for **n**. If you do perform a "blind update" you should allow the machine adequate time to finish. **Please note that on an** Issue **4, the average AB update time is 15 minutes from the time you press y so allow about 20 minutes before turning the power off.** ### Multicore (Extra Cores) update The Extra Cores update deals with the optional third party cores the ZX Spectrum Next accepts. The process is similar with two exceptions. You will need a file called **CORExxx.BIT** where **xxx** is a number from **001** to **031** instead of the **TBBLUE.TBU** placed in the root folder of your **System/Next™** distribution and you enter it by pressing and holding **C** instead of **U** while in *NextZXOS*. Every other step is exactly the same. Your 3rd party core will come with instructions on what to do and how to start the core. Generally speaking, files specific to that core go under the **c:/machines/** folder, into one subfolder specific to that core. So if, for example, a QL core was released, you would find all pertinent files into **c:/machines/ql/**. ### Updating the firmware In ZX Spectrum Next terminology, *firmware* is the file called **TBBLUE.FW** that's located in the root folder of the SD card that holds your **System/Next™** distribution. It is impossible to start the machine without it, as it's a special program that configures all aspects of the machine regardless of personality and core. To update it, you only have to copy the new version over the previous TBBLUE.FW version. The current FW version is reported on the boot screen. See your *Quick Start Guide* to see how the core gets reported while booting.