help installing 2mb A500 trapdoor expansion

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DonutKing

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Ive picked up a trapdoor expansion for my Amiga 500. Its apparently an Elbox A507.zip but I cant find any info on it.
It supposedly provides 1mb chipram and 1.5 mb slow ram.

It comes with a gary adapter with 4 wires, the top two are labeled JP8L and JP8R. That bit is fairly straightforward.

The next one is labelled JP2 and Im a little confused which pad on JP2 its supposed to go to. Should I just attach it to the middle pad? I haven't modded my A500 at all, so if I want 1mb chipram do I need to cut the trace connecting the center and lower pad, and connect the center and top? Do I need to cut JP7?

Final wire is labelled A and there is an A jumper on the expansion so that bit is easy.

There is a WR jumper on the expansion, can anyone tell me its purpose?
Pictures that were provided to me are here http://www.aukcjoner.pl/gallery/015724744-.html#I4

Thanks!

- - - Updated - - -

Here's a photo. Note the two jumpers on the expansion, the inner is WR and the outer is A.

 
Nobody can help?

I tried installing it:
-JP2 wire soldered onto center pad of JP2. Cut trace between lower pads and bridged the top two pads.
-JP8R wire soldered to right side pad of JP8
-JP8L wire soldered to left side pad of JP8

No boot - black screen.

Tried cutting JP7A trace on lower pads - no difference

Tried removing Gary adapter and leaving wires in place - boots but gives 'SOS Error' about no memory.

Any help?
 
OK I managed to sort it out.

Trick is to solder JP2 wire onto center pad and cut the trace so none of the pads are bridged.

JP7A didn't seem to make any difference if it was bridged or not.

Now I get 1.5MB other/slow RAM, 1MB Chip RAM and with the ACA500, 1.5MB Fast RAM.
This lets me run most WHDload slaves without any stuttering or slowdowns like I'd get with an ACA1232.

I don't know what the WR jumper does, but when I was testing with the jumper closed I found that sanity's Optimum ****up demo wouldn't run, it would just get stuck on decrunching. With the jumper disabled the demo worked fine... can't see any other difference in memcheck or sysinfo.
 
I just woke up... realised I have one of these stashed away somewhere. Reason it was put away, no instructions so left it for another day. Maybe I should find it and see if it works.

EDIT: Do you know the revision of your A500 board?
 
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Yep my board is rev 6A

Id still like to know what the WR jumper and the other solder pads on the gary apapter are for...
 
Good as I have a pair of 6A's here, one of them needs its agnus socket replacing before I start doing anything.

As for the gary board. Those solder pads defo look like config stuff! Have no clue what 3 and 4 does, but 2M must be 2megabyte surely? Gnd is obvious. Where is the WR jumper? is that the two jumpers near the zip chips? I need to find the board I have here, afaik mine has a fly lead attached to the board which looks a bit... well its ready to fall off so needs re-doing. I cannot remember where it came from but I do remember getting a dual-kickstart switch with it. I am planning to spend some time fettling and fitting this stuff. I shall do some pictures as I go :)
 
Yep the WR jumper is near the ZIP chips. The other jumper is A, and the A lead from the gary adapter is connected here. I don't know why it was supplied with a jumper on it, unless removing the fly lead and closing the jumper disables the expansion.

I wouldn't know how to use the 2M solder pad, maybe you need a 2M Agnus for that.
 
The seller sent me the manual in polish: http://www.exec.pl/forum_watek.jsp?p=401&s=0

Basically I've got the soldering right. The WR jumper allows the time and date to be changed if an RTC chip is installed on the expansion (mine doesn't have one). Why that made a particular demo crash, I've no idea.
The 2M jumper is named misleadingly. It limits the memory expansion to 512KB when it is closed, and allows the full 2MB when it is opened (default).

Holing the mouse and joystick buttons as power is switched on allow different configurations - by default it gives 1MB Chip, 1.5MB slow. Holding joystick fire gives 0.5MB Chip and 1.8MB slow. Holding left mouse button and joystick fire disables the expansion completely (only 512KB chipram).



Here's a google translated version of the manual:


if someone needed for the future INSTALLATION INSTRUCTIONS FOR EXTENDING THE MEMORY ELBOX RAM 2 MB (A701B.zip) v2.5
There are two ways to install memory expansion Amiga: -
Easy installation, after which the Amiga reports a 2.3MB memory configuration CHIP 0.5MB, 1.8MB FAST. -
Install full, to comply with the need to use a soldering iron. Amiga reports a 2.5MB of memory which can be configured from 0.5MB to 2.5MB. If you have decided to install a stripped lower all activities marked with *.
1) Turn off the Amiga from the network and disconnect all devices connected to the Amiga: power supply, monitor, etc.
2) Turn the Amiga upside down. Remove the three screws at the upper edge of the Amiga and the three screws at the bottom hem.
3) Remove the lid of the expansion and replace the connector board memory expansion. Replace the battery door.
4) Turn the Amiga back and remove the top cover.
5) Disconnect the keyboard, unscrew the four screws that secure the metal shield and remove it. Note: Remember the direction connecting the keyboard connector.
6) * Read the version number plate of your Amiga. It is located in the corner of the plate between the disk drive and memory expansion pocket. Read the number AGNUS. It is the only square chip in the Amiga. Note: If the version number of your plate is lower than the REV 6 or arrangement AGNUS number is lower than 8372, you leave all the steps of the letter "a".
7) Find 5719 GARY system on board the Amiga. It is located in the middle of the plate. Carefully remove it from the socket by gently questioning him flat screwdriver. Note: Remember the orientation of the GARY.
8 In place of the insert plate GARY socket for GARY system so that wires coming out towards the 8364 PAULA.
9) Put the plate with stand GARY system. Note: If the CD Amiga is arranged as in normal operation of the computer, the inscriptions on the systems need to be upside down.
10) On the upper two pins located in the corner of the plate extension (labeled A) suppose jumper connected to serial communication line from point A coasters GARY system.
11) * Find a jumper JP8 on board Amiga. Jumper JP8 is a 3-point jumper and is located at 8520 ODD CIA system (A) here for ladder resistors RP501. Strip the end of the Kabelka JP8R (marking on the PCB socket for system GARY) and solder it to the right point jumper JP8. If you have a disc REV 5 Kabelka solder to the tip of the soldering point located between the inscriptions EMI519, EMI521 just behind the ladder resistors RP501).
12a) * Strip the end of the Kabelka JP8L (marking on the base plate of the system GARY) and solder it to the left point jumper JP8. 13a) * Find the jumper JP2 on the board Amiga. It is located on the right side of the 68000 microprocessor. JP2 is a three - point armature, wherein the two points are connected. Cut gently connection between these two points. Strip the end of the Kabelka JP2 (marking on the PCB socket for system GARY) and solder it to the mid-point jumper JP2 on the board Amiga.
14) Tighten the screws a metal screen, connect the keyboard, suppose the top cover and tighten the screws on the bottom of the Amiga.
CONFIGURING MEMORY Amiga. Possible memory configurations are as follows:
1) 0.5 MB CHIP, 0 MB FAST, if in the course of switching the Amiga are pressed the left mouse button and joystick FIRE simultaneously.
2) 0.5 MB CHIP, 1.8 MB FAST, if in the course of switching Amiga FIRE button is pressed the joystick.
3) 1 MB CHIP, 0 MB FAST, if in the course of the Amiga switch is pressed the left mouse button.
4) CHIP 1MB, 1.5MB FAST, if in the course of switching Amiga No key is not pressed. Note: Holders of Amiga Agnus number lower than 8372 can not use the third and fourth modes of operation.
Note: The operating system of the Amiga is designed so that checking the configuration after power is held only when the dynamic memory there is no information on the status of the Amiga before switching off. To obtain this assurance Amiga should be off for longer than 20 seconds. Note: Remembering the Amiga systems addressing memory configuration takes place not only on power but also after the reset of the keyboard. This means that if we want to maintain compliance with the addressing system configuration information in the operating system, when you reset the keyboard press the buttons as mouse and joystick as he remembered them operating system after power-up.
Memory expansion A701B.zip allows you to simulate the extension of 0.5 MB. To use this option, it is necessary to mount an external switch connected to two points kabelkami 2M and GND plate with socket for GARY system. Short circuit switch these two points results in the following memory configuration extensions: 1) 0.5 MB CHIP, 0 MB FAST, if in the course of switching the Amiga are pressed the left mouse button and joystick FIRE simultaneously. 2) 1.0 MB CHIP, 0 MB FAST, if in the course of switching Amiga FIRE button is pressed the joystick. 3) 0.5 MB CHIP, 0.5 MB FAST, if in the course of the Amiga switch is pressed the left mouse button. 4) 0.5 MB CHIP, 0.5 MB FAST, if in the course of switching Amiga No key is not pressed.
CLOCK extension may be equipped with a clock supported battery. * To read a clock is used Amiga SetClock LOAD instruction. * To protect against accidental recording clock is used jumper WR. If jumper WR is compact, it is possible to change the time, if it is gaping, you can not change the preset time. * In case you need to change the date or time must be DATE command to set the time and give the command RESET SetClock SetClock SAVE. Description of these commands, see the instructions for the Amiga computer.
 
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Brilliant stuff :D

I would like that A701B.zip if it is ok? I shall try and find my expansion tonight. Hoping its in here somewhere boxed up.

EDIT: Typical me lol! A701B.zip is the model of the memory expansion not the manual is it not? I assume Elbox made a DIP version of this or even a SIMM version?

EDIT2: Hmmm this thing can have a clock & battery fitted :D time to rummage my parts bin and see if it can be sorted out.
 
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