A1200 8MB Fast Memory Expansion

A1200 8MB Fast RAM Memory Expansion

Introduction

This memory expansion expands your Commodore Amiga 1200 computer's memory to a total of 10 Megabytes (MB). Extra memory is essential for many games and applications which require or can utilise more than the standard 2MB of RAM.

The 8MB memory increases Fast Memory on your computer and has the added benefit of inceasing the computer speed to 2.91 Millions of Instructions Per Second (MIPS).

Real Time Clock Installed

Top Side With Second Clockport

   

Hardware Installation

1 Power down the Amiga and monitor. Unplug all cables from the Amiga.

2 Anti-statically discharge yourself before handling the device. It is recommended to use an E.S.D. wrist strap for the installation process (such as Amiga Kit product code TLSASW001).

3 Turn over the Amiga and remove the plastic trap door cover by using a small coin/flat blade screw driver to gently lever open the plastic latch.

4 Align the memory expansion's 150-pin expansion connector with the gold contacts on the motherboard and push it on until fully in place. Do not push the expansion onto the motherboard's gold contact at an angle as this could bend or damage the pins in the connector. If the metal upper RF shielding is obstructing the installation of the card, then it may need to be gently bent upwards. It can also be loosened by opening the computer and loosing the securing screw.

5 Replace trap door cover, turn over, connect all cables and power on.

   

Maths Co-processor (FPU) Installation

The memory expansion accepts a Motorola/Freescale/NXP 68882 Maths Co-processor with a PLCC package. This can significantly accelerate Floating Point Math operations.

The Maths Co-processor is sensitive to static electricity and can be damage if anti-static measures are not taken before handling the component. It is recommended to use an E.S.D. wrist strap for the installation process (such as Amiga Kit product code TLSASW001).

One corner of the Math Co-processor chip has a cut-off edge to denote it's orientation when installed. The socket on the memory expansion has a matching cut-off. This cut-off corner is indicated with a rectangular symbol next to it. There is also an arrow symbol in the socket to guide the orientation of the chip.

The chip will simply push into the socket. If it is necessary to remove the Math Co-processor chip, always use a PLCC Extraction Tool (such as Amiga Kit product code TLSPLCCEX). This avoids damage to the PLCC socket.

A crystal oscillator can regulate the speed that the Math Co-processor will operate at. This can be either an 8 or 14 pin crystal oscillator (5 volt) with a maximum frequency of 40Mhz. It will need to be soldered into place at location X1 on the memory expansion noting the white spot that is printed onto the silkscreen to indicating orientation of pin 1.

Finally the FPU jumper settings need to be set to either EXT, INT or OFF. If the installed crystal oscillator is to be used for the FPU, then the EXT jumper should be set. If a crystal oscillator is not installed, then the INT jumper should be set. The frequency of the Maths Co-processor will then set to the internal frequency that the computer's CPU is operating at.

The OFF jumper disables the Math Co-processor or is set if not installed.

   

Real Time Clock Module Installation

The memory expansion has a 22-pin header which is compatible with the optional Real Time Clock Module (Amiga Kit Product Code: ADARTCMOD).

The Real Time Clock Module is installed by pushing it firmly on to the 22-pin header marked RTC Module following the white outline 'L' shape printed on the memory expansion for guidance on orientation.

Do not connect any other Clock Port expansions to the RTC Module connector except for the compatible L-shaped Real Time Clock module.

   

Memory Options

There are three memory options selectable by the RAM jumper on the expansion board:

8MB Mode: the full 8MB Fast Memory will be available. PCMCIA port will be disabled.

5.5MB Mode: 4MB Fast Memory and 1.5MB Ranger Memory are available. PCMCIA port will be active when software patch is run at system boot.
(Ranger patch file required to use Ranger memory, else the system will be unstable)

4MB Mode: 4MB of Fast Memory is available. PCMCIA port is active and compatible.

   

Features

• 8MB RAM to boost total system memory to 10MB

• Memory auto configures with no drivers required

• Socket for optional 68882 Maths Co-processor (Floating Point Unit): up to 40Mhz maximum speed with matching crystal oscillator

• Header for optional Real Time Clock module

• Additional Clockport to offer a second clockport header.

   

Revisions

Version 1.0: Released in March 2020. Initial production run.

Version 1.5: Released in July 2020. Second production run. PCB card reduced in dimensions.

   

Troubleshooting

If you have problems with the card not being recognised by the computer then review these troubleshooting tips:

• When installing ensure you install it flush and not at any angle. If it is installed incorrectly then the pins on the edge connector may become bent.

• Clean the top and bottom of the gold edge connector of the motherboard with Isopropyl Alcohol (IPA). Your motherboard is probably over 25 years old and it is likely that the connector has become dirty/corroded over this long time.

• Do not insert the card fully: pull the card off the edge connector by 2mm.

   

Where to buy

This product can be purchased on Amiga Kit Amiga Store:

A1200 8MB Fast RAM Memory Expansion (FPU Upgradable)

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