Guide: Fitting the SEC Booster to the H4

[Icky]

Here is a small guide on how to fit the SEC booster to the H4. All information and @exxos' blog of the SEC booster progress can be seen here - https://www.exxosforum.co.uk/forum/viewt ... p?f=6&t=45

When using the SEC Booster in the H4 the first step you will need to do is to remove the PLCC CPU from its socket as we will be using the SEC CPU on the booster board.

The SEC booster board will use one of the four expansion sockets on the H4 and there is the need to connect two wires between the booster board and the H4. There are two pads on the booster situated at the bottom just to the right of the SEC chip. The lefthand pad goes to the righthand pad of JP5 on the H4 and the righthand pad goes to the righthand pad of JP13 on the H4.

Screenshot 2020-01-17 at 07.02.42.png

In addition the booster board has TOS 206 decoding so you can replace the 102/104 TOS ROM in the H4 for a 104/206 TOS ROM if you wish. If using one of exxos' rooms from his store https://www.exxosforum.co.uk/atari/store2/#0054 then the ROM selection jumper on the H4 will be TOS 104 when closed and TOS 206 when open.

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[exxos]

:bravo: :goodpost:

[PhilC]

Just tried installing the booster on my first H4.

If I have a disk in the drive it will fail before ram check on TOS 2.06 but with no disk in the drive it boots to desktop and then bombs when I put a disk in the drive and try to access it.

Got to get some more work done now, so will have a look later but any thoughts?

p.s. glitter removed and jumped to check if thats what the problem was.

[exxos]

@PhilC I will PM you a updated jed later. Its not helping @Icky with his issues so far though :( works fine on my STFM now though :lol: