[cottonseed]

Unfortunately IceStorm has only reverse engineered the 1K and 8K, not the 4K.

[cliffordvienna]

There is no 4K die. The 4K chips are using 8K dies, the lattice software limits the number of usable LUTs to 4K. IceStorm will give you access to all 8K LUTs in the device.

[cottonseed]

I didn't realize that. Thanks for clarifying, Clifford!

[ElaineB]

Really? On the http://www.clifford.at/icestorm/ IceStorm site - If you look carefully at the table of supported devices - the ICE40HX4K-144 is there - 2 rows from the bottom

[rwmj]

Am I right in thinking 8K refers to the number of LUTs/cells? If so I won't be fitting the Rocket RISC-V design in one any time soon. Although it's a good start - I'll be very happy to see the back of Xilinx Vivado awfulness one day.

[cliffordvienna]

PicoRV32 (https://github.com/cliffordwolf/picorv32) and ORCA (https://github.com/VectorBlox/orca) are two RISC-V implementations that nicely fit in ~2000 iCE40 LUTs. UCB-BAR V-Scale (https://github.com/ucb-bar/vscale) fits in ~4000 iCE40 LUTs.

[edwintorok]

There is a Pico Risc-V that fits in ~2000 LUTs that can be built for the ice40: https://github.com/cliffordwolf/picorv32 https://github.com/cliffordwolf/picorv32/blob/master/scripts...

[cottonseed]

I stand corrected. See Clifford's other comment in this thread.