SuperAMS

The SuperAMS is an expanded memory SYSTEM for the TI-99/4A. SuperAMS will only work with an original 99/4A, not with a TI-99/4A clone, Geneve, or the TI-99/4. This requirement is stressed because the card is more than just a piece of hardware, it is full functioning system that allows programmers and regular users to enjoy the enhanced and improved power of the TI-99/4A, through the use of expanded memory.

Can I buy a parts kit for the SuperAMS?

Yes. Richard Bell (swim4home@aol.com) sells these kits. Here are the kits and prices:

• 256K version - $28 + ship
• 1MB version - $48 + ship
• 14 sockets for above packages - add $6 to above prices

If you want to buy them from an online vendor you can use the parts list that is in the SuperAMS portion of this FAQ. Jim Fetzner mentioned Unicorn Electronics and I personally ordered (2) kits from them with the sockets. The price for these kits was about $25 which is really cheap. You still need to purchase your (2) 128K or (2) 512K SRAM chips to make your board a 256K or 1MB card. I found these chips at Jameco for about $10 and $20 each respectively. So the the SRAM will cost $20 for 256K or $40 for 1MB. If you can get in on the group buy from Richard Bell then it would be worth while!

Is there a part list for the SuperAMS board?

Yes. Jim Fetzner posted this on the TI mailing list.

DESC - PART# - QTY

• 14 pin socket - (MT14) - qty 5
• 16 pin socket - (MT16) - qty 2
• 20 pin socket - (MT20) - qty 5
• 32 pin socket - (MT32) - qty 2
• 40 pin socket - (MT40) - qty 1
• +5V Regulator, 1 Amp - (7805T) - qty 1
• .1mf 50V monolithic cap - (CPM.150) - qty 4
• 100mf 16V radial electrolytic cap - (CPE10016) - qty 1
• 47mf 16V radial electrolytic cap - (CPE4716) - qty 1
• Memory Mapper Chip - (74HCT612) - qty 1
• Octal Bus Transceiver - (74HCT245) - qty 1
• 8-bit Magnitude Comparator - (74HCT688) - qty 1
• Octal Driver - (74HCT244) - qty 3
• Quad 2-input AND Gate - (74HCT08) - qty 1
• 8-bit Addressable Latch - (74HCT259) - qty 1
• Hex Inverter - (74HCT04) - qty 1
• Quad 2-input OR Gate - (74HCT32) - qty 1
• 3 to 8-line Decoder/De-multiplexer - (74HCT138) - qty 1
• Quad Bus Buffer Gate - (74HCT125) - qty 1

Note also that C-1 is the 47mf cap and that C-3 is the 100mf cap, and that the four .1mf caps are not marked--you just have to find their pad pairs. It is best to use a photo of a completed card to see where those four are.

Choose your memory chips separately, either 128K or 512K, I didn't list those above.

What are PASS and MAP modes for the SuperAMS?

PASS mode makes the SuperAMS operate like a standard 32k card, no more and no less.? MAP mode allows progams to take advantage of all the expanded memory.? It is important to understand that programs must be written to take advantage of this, if not then they cannot use it. Original information from J.W. Krych - (c) 1995

What are some of the technical aspects of the SuperAMS?

• replaces any and all 32k cards in the PEB
• uses CRU address >1E00
• to switch between MAP and PASS modes uses the >4000 space for memory mapper
• register uses the 74HCT612 Memory Mapper for expanded memory (a one-chip solution, 74HCT612 is the low-power version fo the 741s612)
• uses 4k page segments (note! in manual programming the page size is that, 4k, with the Linker system program modules can be from 4k up to 24k in length.)
• is the first memory system to not utilize a DSR, Device Service Routine, for the expanded memory access.
• The upper 24k of the 99/4A is mapped out (registers A-F), and the lower 8k is mapped out (registers 23)

What does SuperAMS offer in expanded memory?

SuperAMS, by it's design, will allow from 128k all the way up to 1024k of memory. 128k and 256k models are built with 128k x 8 SRAM chips.? 512k and 1024k models are built with 512k x 8 SRAM chips. Original information from J.W. Krych - (c) 1995

What happens to the 32K card when using a SuperAMS card?

The SuperAMS is a replacement for the 32k memory card so it functions as the 32k card plus the additional expanded memory. Both cards cannot exist in the system at the same time. Original information from J.W. Krych - (c) 1995

What is expanded memory?

Expanded memory is anything that is above the standard 32k card that Texas Instruments and other third-parties designed and sold. This can be as little as 4k more or on up towards 1024k. Original information from J.W. Krych - (c) 1995