SY99 8MB Magic Memory Board Ordering

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STOP!Installation of the SY99 Magic Memory Board (MMB) requires soldering 2 wires directly to the pins of a surface mount IC on the Yamaha SY99. These pins are just 0.4 mm (0.015") wide, and are spaced just 1.27 mm (0.05") apart.

You may also have to desolder a 32-pin EPROM chip if you have a late-run SY99.

Do NOT purchase this kit unless you have the skills necessary to install it, or you have access to a competent synthesizer technician who can install it for you!

Which option should I buy?

The version of Operating System (OS) in your Yamaha SY99 determines the package you will need to purchase.

To determine your OS version: While pressing the [Voice] switch, press and hold the [INTERNAL] Memory switch, then the Patch [1 (OP 1)] switch. The version of the MAIN ROM should be displayed. The sequencer ROM version does not matter. Press [EXIT] to return to the main screen, or power off your SY99.

The table below tells you which package to order:

OS Version Recommended Package
MMB with EPROM, CPU, & PLCC Extractor
1.57 MMB with EPROM and socket
1.60 MMB without EPROM

Some of the 1.57 SY99s have the CPU and EPROMs soldered directly to the DM2 board. Because of this, we ship a Mill-Max turned pin socket with every 1.57-OS order.

The CPU upgrade for versions <1.57 is required because the initial boot code for the SY99 is burned directly into the CPU. And for OS 1.57 and 1.60, the older CPU code is not compatible with the newer EPROMS.

Unfortunately, burning code into the CPU is a one-time process. Worse, H8/532 chips are no longer being manufactured, so the cost of CPU upgrades is high. Sorry about that - it's out of our control. We're selling these CPU upgrades at cost. If we run out of blank CPUs, a prominent notice will be posted on this page, and any orders for kits with CPUs will be refunded in full with an sincere apology.

PLCC Extractor

If you need a CPU upgrade, you'll need a PLCC extractor (pictured above). This tool clips underneath two corners of the CPU and prises it out of the socket with no damage to the socket itself. Other techniques (like using a screwdriver) can damage the socket - a costly repair. If you already have one, put in the comments field on your order you don't need one and we'll leave it out.


What about my existing SYEMB05 expansion boards?

Unfortunately, if any are installed, you will need to remove your SYEMB05 boards before installing the MMB. The MMB fills the entire 8MB memory space (less the on-board internal 512KB RAM) on its own. Adding functionality to the MMB to allow co-existence with SYEMB05 boards would complicate the design and increase the price for everyone. We're sorry about this, but we think you'll appreciate the reduced cost.


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