So, you have an AD-600A but you can't access the Loophole Menu? That means you have a later version of the firmware where the hidden menu has been taken out because of pressure from the authorities. In this case you have to replace your firmware chip with one that will allow you to access the hidden menu. This involves a bit of electronics know-how. So if you don't feel confident about doing this DON'T DO IT!

Also, there is still this misconception that the Loophole Menu is the "biggest and best". Nothing could be further from the truth. The loophole firmware is old and does not support all types of DVD, especially those newer ones that has "Seamless Branching" features. Sooner or later you will have a DVD that won't play. Try playing "Dinosaur" and you will see what I mean - 1/2 way into the movie and the plyer quits. Also the old Loophole firmware does not play MP3 properly and has a problem with sound and video being out of sync. There is a lot better firmware out there (N6 and GK600B) that can be made Region Free and Macrovision off permanently and do not suffer from RCE problems (discussed here). Therefore a Loophole Menu is not needed.

However if you STILL want Loophole firmware here is the procedure:

First, let's have a look at where the firmware chip is....

The picture on the left is an ES4308 processor player. The one on the right is an ES4318 processor player. The firmware chip is highlighted in yellow in both pictures. Read the sticker on your chip. It should say something like "A6" or similar. This is the firmware version number. It may even be an "N" with a number after it. If you have a A9, A10, A11, N1-2, N1-4, N3, N4, N5, N6, N12 or GK600 version then this is why you can't see the hidden menu and your only option is to change the chip. The last version before the hidden menu was deleted is known as "A8". There is also a "A7" for the Apex but this is for a special video chip that was used.

What is the talk about a "Special Video Chip?". For some reason a slightly different video chip was used in the AD-600A for a while. The standard video chip is the "ADV7170" and is located here:

However, maybe due to a shortage, another similar chip the "ADV7175" was used instead. Even though basic operation is the same it is different enough to need it's own special firmware - "A7" and "A10". "A7" has Loophole Menu and "A10" does not.

For those who are curious about the Hiteker in Australia, I bought mine in late August 2000 from Radio Parts in Melbourne, Victoria and it still had the hidden menu. The firmware revision was "A6" which is pretty much the same as the Apex "A8" but with a different background. These days the Australian Hiteker is the newer board and has GK600 firmware.

Unfortunately, most firmware chips installed in the AD-600A from the factory is a 27C040 4Mb (Mega-Bit) One Time Programmable (OTP) memory chip. That means you can not change it's program. However, you can obtain a pre-programmed copy of an earlier version of the firmware from various sources on the net, even fancy "dual boot" types which have two different firmware versions for the best of both worlds and you simply flick a switch to select what version you require. Alternatively, if you have access to an EPROM programmer you can buy a blank chip and program your own. The blank EPROM you are looking for is a 27C040 type and these are available from many electronics parts suppliers at reasonable prices. Visit my FREE PROGRAMMING page for more information.

NOTE: Some of the later AD-600A players have a Flash ROM fitted. If you lift the version sticker and see "27F040" or "29F040" (the "F" means Flash) then you are in luck! Flash ROM's are eraseable so you can re-program your chip with different firmware, meaning you don't have to buy another chip. If however you do not want to re-program your chip for safety then just buy a 27C040 EPROM. You can buy 27F040 Flash ROM's but they are more expensive. Again, my FREE PROGRAMMING page has links on where to get the chips from.

Once you have your "A8" firmware (or "A7" if your player has an ADV7175 video chip) BIOS chip it is a simple matter of carefully lifting your old BIOS chip out of it's socket and putting in the new one **READ NOTES BELOW if you are doing the modification to an ES4318 processor player. Remember to note the notch in one end if the chip as indicated by the yellow highlights in the two picture above outlining the firmware chip. You must use this as a guide because even though the chip can go in the socket both ways, only one way is correct and remember:

Putting the chip in the wrong way will damage your player, so be careful before you power up!

Once you are sure you have installed the chip correctly all that is left to do is turn on your player and set up the hidden menu as described above.

** There is a slight difference if you have an AD-600A player with an ES4318 processor (the big square chip) with firmware versions N2, N3, N4, N5, N6, N1-2 or GK600 series firmware as opposed to an ES4308 processor with firmware A6 to A11. The pictures above show the different boards. The later version of the AD-600A player with an ES4318 needs a little more work to make it function with "A8" firmware because it is missing the two Static RAM (SRAM) chips at locations U5 and U6, as highlighted in the above picture with a red box showing where the chips should be. If you just install an "A8" chip in a ES4318 equipped player without the SRAM at U5 and U6 the player just crashes. The solution here is to install the SRAM chips first into the blank locations at U5 and U6. You will need two ISSI IS16C256AH-15 Static RAM chips (or equivalents..... read on). After installation THEN you can use A8 firmware.

Technical specs on the IS16C256AH SRAM can be found HERE.

A Preliminary data Sheet on the ES4308F can be found HERE.

Detailed pictures and more information can be found HERE. This link also contains a detailed list of equivalent SRAM's you can use. An alernative description of how to do the SRAM modification can be found HERE.