Tag: ram

Adds up to the Z80's full 64K addressable RAM with selectable start address.

Current kits are offered with 32K or 64K and Standard or Enhanced Bus headers. The listing is for the memory module only; a CP/M setup also needs the documented Pageable ROM and other core modules.

Adds banked memory for running RomWBW, CP/M, and Z-System.

The current kit is the memory configuration used by RC2014 Zed and Zed Pro. It replaces both separate ROM and RAM modules in a Classic II or Pro; a Mini can use it only after its onboard ROM and RAM chips are removed.

Replaces the Amiga 3000's ZIP-package Fast RAM with standard 72-pin SIMMs.

Rabbit Hole Computing marked the bare PCB sold out on 2026-07-24. The PCB did not include SIMM sockets, adapter pins, capacitors, resistor, LED, or SIMMs. Its linked project page now returns 404, so verify that a used board includes the build information and all required parts.

Combines 8 MB of fast static RAM with an optional 512K boot ROM and built-in IIgs debugging software.

The card was out of stock on 2026-07-24. The optional ROM portion makes the assembly wider than a plain memory card; check clearance around long slot cards, especially in slot 7.

Adds 1 MB of banked RAM to an Atari 1200XL or 800XL with a 30-pin SIMM and custom refresh and bank-selection logic.

The archived article provides the circuit discussion, 1200XL connection table, SIMM pinout, and software notes but describes the 800XL only as having similar connection points. It is an advanced historical wire-and-perfboard build. The author reports that the SpartaDOS cartridge does not function with this configuration and that ordinary SpartaDOS and much commercial software see only a 320XE-style subset; MYDOS 4.5.1M or newer needs the documented page sequence.

Expands a 16 KB Atari 600XL to 64 KB with two 41464 DRAMs and three wiring changes.

The archived instructions call for two 41464-10 or compatible DRAMs, hookup wire, soldering tools, and optional sockets. Chips may need desoldering, several pins and resistor leads must be isolated, and fine motherboard traces are exposed; the author explicitly says to attempt it only if the diagram is understood and at the builder's risk. This is a historical modification guide, not a current kit.

Expands eMate 300 system RAM and internal flash storage while widening both buses to 32 bits.

JCM showed 54 assembled DRAM-plus-flash modules in stock on 2026-07-24. Installing or removing this version causes a full factory reset and erases internal storage, so back up first. The developer also reports that repeated module swaps on a tester preceded lost calibration data and disabled battery charging.

Recreates the original 512 KB memory expansion for Franklin Ace 2x00 computers.

Human review confirmed that Board Only, Kit, and Fully Assembled variants could all be ordered on 2026-07-24. The page does not say that Board Only includes components; only the kit and assembled options are stated to include the full 512 KB. The board is fully tested in a Franklin Ace 2200; the broader page claim is Franklin Ace 2x00.

A newly made 1 MB SIMM for the Atari 520STE and 1040STE memory sockets.

The product page exposed a login-or-register-to-buy path on 2026-07-27. It explicitly names the Atari 520STE and 1040STE and loosely says it works in many more systems; only the two named computers are indexed here. Check the computer's existing SIMM population and desired total memory before ordering modules.

Replaces Atari 8-bit dynamic RAM with modern SRAM or configurable FPGA-managed PSRAM in three current versions.

All three memory variants exposed login-or-register-to-buy paths on 2026-07-27. Installation goes under the CPU and may require removal or isolation of the original DRAM, desoldering, new sockets, and EXT_SEL or CAS_INHIBIT connections. The Professional version also uses an MMU adapter and its page says to install the latest firmware before use. The optional Freddy Module v2 cannot operate alone: the seller requires the basic SRAM module first and says VBXE owners do not need the Freddy replacement.

Adds a vintage 1 MB banked-memory board to an Atari 800XL or 1200XL with several selectable PIA banking configurations.

Only archived installation instructions and the used market were verified. Installation requires the original Newell board or a faithful equivalent, memory devices, extensive motherboard wiring, isolated IC pins, and model-specific changes; a 1200XL also needs three address-trace changes. The recommended banking method preserves OS control and ANTIC banking but repurposes other PIA bits and may require BASIC and diagnostic switches. The top RF shield may no longer fit.

Uses a 1 MB 30-pin SIMM and GAL controller to add switchable Compy Shop or Newell/RAMBO banked memory to Atari XL and XE computers.

The Polish project page publishes a schematic, GAL JEDEC file, utilities, parts list, full 800XL and Freddie-equipped 800XLF instructions, startup tests, and timing troubleshooting. Installation is highly invasive and may require trace cuts, lifted or bent IC pins, motherboard timing changes, and RAS-delay tuning for a particular machine. The page groups the 600XL and 1200XL with older 800XL memory-control hardware but does not provide separate step-by-step guides for those models. No explicit project license was verified.

Adds either 4 MB or 8 MB of low-power fast RAM to an Apple IIgs.

The GGLABS Tindie store was taking a break on 2026-07-24, so neither capacity had a current order path. Choose one capacity; both occupy the dedicated memory slot.

Combines 128K of Flash ROM and 128K of paged RAM for RC2014 systems, including CP/M configurations.

The project page provides firmware, a schematic, PCB files, Gerbers, and supplier links. A later SC707 design also exists, but SC152 remains documented and buildable. Keep the Flash write-protect jumper in its normal read-only position except when programming it.

Adds 128K of Flash ROM and 128K of paged RAM for a CP/M-capable Z80 system.

The project provides Small Computer Monitor S8 firmware, a schematic, Gerbers, PCB design files, and kit or bare-PCB suppliers; an assembled version is not offered. Observe the Flash write-protect jumper and avoid function conflicts with other system memory modules.

Combines a Z80, paged RAM and Flash, clock, reset, and serial terminal on one RCBus module.

The project provides firmware, a schematic, Gerbers, PCB design files, and kit or bare-PCB suppliers; an assembled version is not offered. SC708 has no automatic power-on reset, so press its reset button after applying power. Avoid duplicate CPU, memory, clock, reset, or serial functions when adding it to a modular system.

Adds 512K of Flash ROM and 512K of banked RAM for RomWBW and CP/M.

The project supplies RomWBW and Small Computer Monitor firmware, a schematic, Gerbers, PCB design files, and links for kits and bare PCBs; an assembled version is not offered. It is intended for the SC706 Z80 CPU module and is not compatible with the SC730 CPU plus MMU module. JP1 controls Flash write protection.

Adds 512K of RAM and selectable 512K Flash ROM to a 20-bit-address RCBus system.

The project provides Z80 and Z180 firmware, a schematic, Gerbers, PCB design files, and kit or bare-PCB suppliers; an assembled version is not offered. Observe the Flash write-protect jumper and select the ROM/RAM arrangement required by the processor and firmware.

Combines a Z80 CPU, 512 KiB Flash, 512 KiB SRAM, clock, reset, and RomWBW paging on one modular card.

Tindie listed the complete Z80-512K kit without an out-of-stock notice on 2026-07-25; complete open files also remain available for both designs. The Z80-CPM store page failed extraction, so no stock claim is made for that variant. Z80-512K builders using its supervisor without a backup battery must short the battery connector as documented.

Publishes an experimental 1024 KB plus 64 KB SRAM expansion board for the Atari 600XL and 800XL.

The author labels the April 2025 post UNDER WORK and calls it a placeholder. A KiCad archive containing the stated schematic and Gerbers is downloadable, but the page provides no bill of materials, assembly guide, firmware, electrical test results, completed installation report, or explicit license. Treat it as an unfinished engineering project for experienced builders, not a validated kit.

Business-card-sized RC2014-compatible Z80 computer with 1 MiB of memory and integrated serial and parallel I/O.

This is a surface-mount self-assembly project with KiCad, Gerber, CPLD, and firmware documentation. Programming its MAX7000AE CPLD requires the older Quartus II 13.0sp1 toolchain because newer Quartus versions do not support the device.

Documents period DIY memory conversions that give an Atari 400 48 KB plus a banked 16 KB or an Atari 800 a 288 KB SuperRam configuration.

These are historical, invasive board-level modifications rather than current kits. Both require extensive disassembly, trace cuts, soldering, stacked or perfboard logic, and staged electrical testing. The authors release the instructions for public use with attribution. The Atari 800 text lists six 41256 DRAMs, while human review found only one 41256 in its rough circuit sketch. The contradiction remains unresolved: do not treat the Atari 800 parts list or sketch as an authoritative build package without reconstructing and checking the circuit.