ARM System-on-Chips

The following is a list of ARM-based System-on-Chips (SoCs) that either have been used in RISC OS machines, are potentially suitable for RISC OS machines, or have been discussed as possible targets for a RISC OS port.

Samsung S3C24xx

Based on ARM9 cores. The only member of this family that is relevant to RISC OS is the S3C2440, based on the ARM920T core.

S3C2440 Features

• ARM920T CPU @ 300, 400, or 533 MHz (400 in A9home)
• 640x480 24-bpp LCD controller (not used in A9home)
• AC97 audio support
• USB 1.1 host and device support

Used in

• Advantage Six A9home

Compatible with

• RISC OS Adjust32 4.4x

Documents

• S3C2440X Product Brief (PDF)

Anyka AK7802

Based on ARM926EJ core, clocked at 248 or 266 MHz. Used in some cheap netbooks, but not suitable for RISC OS applications due to poor performance relative to other SoCs currently available, and poor documentation. Windows CE is the only supported OS.

Features

• ARM926EJ CPU @ up to 266 MHz
• 800x480 LCD controller
• USB OTG and host support (unknown version)

Documents

• Anyka AK7802 product page

Texas Instruments OMAP3

Based on an ARM Cortex-A8 core, different models have different features including a DSP and PowerVR 3D graphics acceleration. OMAP34 and 36 models are primarily intended for handset (cellular phone) applications, and are not listed below. The OMAP35 is derived from the OMAP34.

Common Features

• ARM Cortex-A8 CPU
• 2048x2048 24-bit display output (74.25 MHz maximum pixel clock, limit @ 60 Hz refresh rate is approximately 1280x960)
• USB 2.0 OTG and host support
• SD/SDIO support

Models

Model	Max CPU speed (MHz)	DSP	GPU
OMAP3530	720	520 MHz TI C64x+	PowerVR SGX 530
OMAP3525	600	430 MHz TI C64x+	None
OMAP3515	600	None	PowerVR SGX 530
OMAP3503	600	None	None

Used in

Development boards

• BeagleBoard (OMAP3530)
• Gumstix Overo (Earth, Air: OMAP3503; Water, Fire: OMAP3530)
• Direct Insight SwiftModule-OM (OMAP3503, 3515, 3530)

Complete systems

• OpenPandora (OMAP3530)
• Always Innovating Touch Book (OMAP3530)

Compatible with

• RISC OS 5.15

Documents

• OMAP3530 and 3525 Datasheet (PDF)
• OMAP3515 and 3503 Datasheet (PDF)

Freescale i.MX515

Another Cortex-A8-based SoC, this one appears to be better suited towards netbook use than the OMAP3, due to including PATA support. However, maximum display resolution is lower.

Features

• ARM Cortex-A8 CPU @ 800 MHz
• 3D accelerator
• 1280x800 24-bpp primary display output
• USB 2.0 OTG and host support
• SD/SDIO support
• ATA-6 (PATA) support

Used in

• Genesi Efika MX Open Client

Documents

• i.MX51 Product Summary

Samsung S5PC100

Similar to TI OMAP3, but may be a better option, as it has CompactFlash support. Currently used in the iPhone 3G S.

Features

• ARM Cortex-A8 CPU @ up to 800 MHz
• PowerVR SGX 530 3D accelerator
• 2048x2048 24-bpp LCD controller, NTSC, PAL, and HDMI 1.2 outputs
• 5.1 channel audio support
• USB 2.0 OTG, USB 1.1 host support
• SD/SDIO support
• CF (PATA) support

Documents

• S5PC100 product information

Marvell Kirkwood 88F6281

Based on Marvell XScale technology (aka "Sheeva")

88F6281 Features

• Sheeva CPU 1200 MHz (ARMv5TE), single issue, 16KB I-Cache + 16KB D-Cache
• 256 KB L2 cache
• DDR2-400 memory interface, up to 2 GB
• 2x Gigabit Ethernet
• 1x PCI Express x1
• 1x USB2.0 host
• 2x S-ATA 2.0
• SD/SDIO support
• S/PDIF I2S audio in/out
• 2x 16550 compatible serial ports

Used in

• eInfochips rd-base ("open-rd" platform)
• eInfochips rd-client (PDF) ("open-rd" platform)
• SheevaPlug

Documents

• Kirkwood Overview
• Kirkwood Product Brief (PDF)
• Kirkwood Hardware Spec (PDF)
• Kirkwood Functional Spec (PDF)