In my first job, I wrote code for a MIPS processor for VoIP phones, then I switched to NEC/Renesas MCUs for CD and DVD players, before going back to Linux and my first experience with an Arm processor: Cirrus Logic EP9307 with a single ARM9 (ARM920T) core clocked at 200 MHz. That was in 2005, and according to Wikipedia various ARM9 cores were released between 1998 to 2006, and now such cores are not recommended for new IC designs with most companies now building their chips around Arm Cortex-A/M/R cores.
At the end of last year, we wrote about Banana Pi BPI-F2S SBC based on Sunplus SP7021 “Plus1” quad-core Cortex-A7 processor with ARM9 and 8051 co-processor. Odd enough but at least the ARM9 core is not the main processor, however, while looking at the upcoming Linux 5.6 Linux kernel log I read an entry about a new SAM9X60 ARM926-based SoC from Microchip.
Quite surprising to have a new ARM9 processor right now, but it should be considered more like an upgrade than a completely new design as explained on Semimedia that first reported about the processor in October 2019:
The chip was upgraded from Atmel’s AT91SAM9260. First, the computing performance of the SAM9X60 has been improved. The previous generation CPU was clocked at 180MHz, and the SAM9X60 was upgraded to 600MHz, up 3.3 times. Secondly, the SAM9X60’s Cache capacity has been expanded to 32KB I-Cache and 32KB D-Cache, which is four times larger than the previous generation…
The SAM9X60 reduces the core operating voltage from 1.8V to 1.2V, and upgrades the SDRAM interface to a (LP)DDR2 interface…
The SAM9X60 adds a 24-bit LCD-TFT interface and a 2D GPU. It can drive up to 1024*768 resolution.
It’s worth noting SAM9X60 is an industrial-grade processor with a temperature range of -40 to 105°C.
Since there haven’t been any other new ARM9 SoC that I know of in recent times, 600Mhz must be a CPU clock record for ARM9 architecture. The system and memory bus are still clocked at 200MHz. The processor should also be more efficient thanks to a lower core operating voltage, and LPDDR2 memory interface. I suppose Microchip introduced this processor for existing customers that may want to upgrade products with improved performance and features while reusing most of the code.
You’ll find the full specifications, datasheet, and documentation for the processor on the product page. Volume pricing starts at $4.34 for 5,000 pieces.
The company also launched an evaluation kit with the following key features and specifications:
- SoC – Microchip SAM9X60-V/DWB ARM926EJ-S microprocessor @ 600 MHz with 64 KB SRAM, 2D Graphics Processor Unit; 228-ball TFBGA
- System Memory – 256 MB DDR2 SDRAM
- Storage – 512 MB NAND Flash, 8 MB QSPI Flash, SD card slot
- Display I/F – LCD Connector
- 10/100M Ethernet Port with Microchip KSZ8081 PHY
- Footprint for WILC3000 Wifi and Bluetooth module
- USB – 3x USB Ports
- Serial – Dual CAN
- Expansion – mikroBUS socket, Raspberry Pi expansion header
- Debugging – Embedded debugger; JTAG and serial headers
- Misc – User buttons, reset and wake up buttons
- Power Supply – 5V via USB or power barrel jack; Microchip MIC2800 PMIC
There’s excellent hardware and software documentation for the board on Linux4SAM Wiki with source code and demo image for Yocto & Builroot built Linux as well as OpenWrt. The product page also comes with documentation, and the board can be purchased on Microchip online store for $260.