Does the L series support single cycle multiply?? tks

[brucemcmillan]

Does the L series support single cycle multiply?? tks

[eduardo_viramon · Accepted solution]

Bruce, the Freescale RM covers the MCU in detail, the core is only superficially documented there because there is already in-depth documentation for the core provided by ARM here:

http://www.arm.com/products/processors/cortex-m/cortex-m0plus.php

And in the ARM Infocenter:

http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ddi0439c/I1010015.html

To your exact question:

Cortex M0+ cores have a 32 x 32 = 32 multiply that can be a single cycle or a 32-cycle implementation, Freescale uses the single-cycle implementation.

[MichaelWang]

Hello,I also have some problems in using the one cycle 32X32 multiplier of Cortex M0+.The MCU I'm using is MKE02Z16VLC2,and the bus clock is 20MHz,I have tested that

a int32Xint32 operation takes 10us,and a int32/int16 takes 14us,is there anything wrong or I haven't used it correctly?

When I use the DSC MC56F8013,there are many functions such as 'mult_r()' which can be used to optimize the program,is there something similar here?

Best Regards!

[ZhangJennie]

kinetis L is based on cotex M0+ core. so it can use  MULS instruction to execute multiply in a single cycle

[brucemcmillan]

Yes, ARM have it as an option on the M0+, and I can't find it specified in the KL25Z documentation, however there are plenty of references to the fast bit-banging, which is also an option.

tks