Difference between nRF51822XXAC and nRF51822XXAA in ROM and RAM during configuration Keil v5

RE: Difference between nRF51822XXAC and nRF51822XXAA in ROM and RAM during configuration Keil v5

Angelo Cotroneo — Wed, 06 May 2020 11:30:16 GMT

Thanks a lot Simon,

Best regards and I hope you are well.

RE: Difference between nRF51822XXAC and nRF51822XXAA in ROM and RAM during configuration Keil v5

Simonr — Wed, 06 May 2020 10:48:08 GMT

Hi Angelo

Yes, this seems correct. The IDE should also give you a warning if there are any conflicts with the RAM/ROM sizes.

Best regards,

Simon

RE: Difference between nRF51822XXAC and nRF51822XXAA in ROM and RAM during configuration Keil v5

Angelo Cotroneo — Wed, 06 May 2020 06:59:01 GMT

Hi Simon,

thank a lot for the link. Here after an example, using the version AA and AC:

"AA" chip Using SoftDevice S120:

RAM: 16K - ROM: 256K

RAM Start: 0x20002800
RAM Size: 0x1800
ROM Start: 0x1D000
ROM size: 0x23000

while

"AC" chip Using SoftDevice S130:

RAM: 32K - ROM: 256K

RAM Start: 0x200013C8
RAM Size: 0x6C38
ROM Start: 0x1B000
ROM size: 0x25000

Correct?

Thanks a lot and best regards

Angelo

RE: Difference between nRF51822XXAC and nRF51822XXAA in ROM and RAM during configuration Keil v5

Simonr — Tue, 05 May 2020 06:50:14 GMT

Hi Angelo

You're absolutely correct, the available flash of a chip is specified in the PS, and the Flash start should be set as specified in the guide according to SoftDevice version you're using.

According to the nRF51822 IC revisions and variants, the flash size is the same for AA and AC chips, although the RAM size is larger in the AC version. So what you'll need to change is the IROM and IRAM start address as well as the IRAM size.

Best regards,

Simon

RE: Difference between nRF51822XXAC and nRF51822XXAA in ROM and RAM during configuration Keil v5

Angelo Cotroneo — Mon, 04 May 2020 11:35:44 GMT

Hi Simon,

thanks a lot for the clarification and link.

I have an other question.

How do I calculate the size of IROM? In the guideline there is written as follow

Flash available - IROM1 Start -> I I think that flash available is in the datasheet while IROM1 start should be FLASH start as reported in chapter 3 of your guidelines.

Correct?

Can you write me an example please?

Thanks a lot and best regards

Angelo

RE: Difference between nRF51822XXAC and nRF51822XXAA in ROM and RAM during configuration Keil v5

Simonr — Mon, 04 May 2020 10:48:00 GMT

Hi Angelo

Please check out our adjustment of RAM and Flash memory guide in order to see what RAM and Flash address the various SoftDevice versions should use, and how to set these in the IDE you're using. If you set the RAM and ROM start addresses correctly in your project, you should be able to advertise and connect via BLE on the nRF51 AA chip as well.

Best regards,

Simon