Tag Archives: ROM

Two bits per transistor: high-density ROM in Intel’s 8087 floating point chip

Ken Shirriff has a great write-up about the multi-level ROM in Intel’s 8087 floating point chip: The 8087 chip provided fast floating point arithmetic for the original IBM PC and became part of the x86 architecture used today. One unusual feature of the 8087 is it contained a multi-level ROM (Read-Only Memory) that stored two […]

rompar: a tool to analyze masked ROMs

You may have seen those highly magnified photos of decapped chips displaying the hardware architecture and wondered what information is represented by the solder-like designs. Adam “Major Malfunction” Laurie of Aperature Labs has developed a software tool to assist in deciphering the bits represented in these highly magnified chip photos. Known as rompar, its a […]

ChameleonOS open source Android ROM

The ChameleonOS dev group has posted the latest version of their open source ROMS for Android devices. They describe: Chameleon OS (or ChaOS for short) is a custom Android ROM that gives the user more control than they can experience on any other Android ROM. Starting with a CyanogenMOD base, we customize each piece to […]

SNES FLASH/ROM runs custom Super Nintendo code

dext0rb from The Electrified Fooling Machine Company has just finished work on a project which allows custom Super Nintendo code to run on an SNES FLASH/ROM. He writes, “I wanted to make and play an updated version of NBA JAM an SNES hardware, so I made this device. Load a game ROM to the device […]

Logic Sniffer upgrade v2.1 released

Package v2.1 is the first official upgrade release for the Logic Sniffer. Download it now at the Gadget Factory. This version has a lot of updates that should fix a bunch of problems in the initial release: FPGA bitstream v2.1 with high-speed SPI connection between the PIC and FPGA. This eliminates most ‘hardware not found’ […]

Logic Sniffer FPGA bitstream/ROM update

This is an old version, see the latest version on the documentation wiki. The Logic Sniffer stores the FPGA (IC3) bitstream in a flash ROM chip (IC2). The PIC microcontroller (IC1) can update the bitstream from a computer using the multi-platform pump-loader application. This feature lets us release FPGA design updates with new features and […]

Bus Blaster: High speed USB to JTAG, SPI, UART

The Bus Pirate can program flash chips with flashrom and debug JTAG devices with OpenOCD, but it doesn’t do these things very fast. It was designed for human-speed interaction. The Bus Pirate is a good way to learn an EEPROM chip, but you eventually integrate the chip in a real circuit with actual code. In […]

Demo: AT45DB041D 4Mbit SPI flash memory

This is an old version, see the latest version on the documentation wiki. This demo is what the Bus Pirate is all about. A AT45DB041D 4Mbit flash memory stores the FPGA design on the open source logic analyzer project currently known as SUMP PUMP. We’ve worked with EEPROMs in the past, but this chip is […]