TMS570LS1227: examples for ADC ( TMS570LS1227, tmds570ls12hdk )

Sebastian Mazur

Part Number: TMS570LS1227
Other Parts Discussed in Thread: TMDS570LS12HDK, HALCOGEN

Tool/software:

Hi,

I use an evaluation board tmds570ls12hdk with TMS570LS1227 microcontroller.

I need to read the results (ADC) from the 'Results’ Memory by accessing the conversion results memory directly (not FIFO queue).
Unfortunately I couldn't find a proper code example.

I used the halcogen tool but the generated code has no function for that.

Where can I find more examples for ADC?

I would appreciate some links or source code examples.

5 months ago

0 jagadish gundavarapu 5 months ago

TI__Guru 70281 points

Hi Sebastian,

I think there is no direct example for this, can you refer below threads and try on your own.

(+) TMS570LS1224: ADC FIFO access - Arm-based microcontrollers forum - Arm-based microcontrollers - TI E2E support forums

(+) TMS570LC4357: ADC read result memory configuration for circular buffering - Arm-based microcontrollers forum - Arm-based microcontrollers - TI E2E support forums

(+) TMS570LC4357: ADC groups channel sequence using Enhanced Channel Selection Mode - Arm-based microcontrollers forum - Arm-based microcontrollers - TI E2E support forums

Let me know, if you face any difficulty in implementation i will assist you on further.

--
Thanks & regards,
Jagadish.

0 Sebastian Mazur 5 months ago in reply to jagadish gundavarapu

Prodigy 90 points

I have resolved the issue. Thank you for providing all the relevant links.

I have a couple of questions regarding the Hercules Safety MCU Demos:

Is the "Hercules Safety MCU Demos" folder the only location containing source code examples for the TMS570LS1227, or are there additional example files available elsewhere?
Regarding the reading of conversion results (single read, one channel, one group):
a) When using the conversion results memory as a FIFO queue, identical results are repeatedly observed across BUF0, BUF1, and so on.
b) When directly accessing the conversion results memory, identical values are observed in memory at different offsets.

Could you please confirm my understanding?
Specifically, is it correct to assume that if an analog value changes rapidly, the results captured in the memory would vary accordingly?
Also, is the organization of the conversion results in reading memory directly inherently structured as a FIFO queue?
Is it possible to somehow limit the number of results in case of reading directly from the memory?

0 jagadish gundavarapu 5 months ago in reply to Sebastian Mazur

TI__Guru 70281 points

Hi Sebastian,

Sebastian Mazur said:
Is the "Hercules Safety MCU Demos" folder the only location containing source code examples for the TMS570LS1227, or are there additional example files available elsewhere?

(+) [FAQ] TMS570LC4357: Examples and Demos available for Hercules Controllers (E.g. TMS570x, RM57x and RM46x etc) - Arm-based microcontrollers forum - Arm-based microcontrollers - TI E2E support forums

In above FAQ, i mentioned how to access all the examples related to the Hercules devices.

Sebastian Mazur said:
Regarding the reading of conversion results (single read, one channel, one group):
a) When using the conversion results memory as a FIFO queue, identical results are repeatedly observed across BUF0, BUF1, and so on.
b) When directly accessing the conversion results memory, identical values are observed in memory at different offsets.

Could you please confirm my understanding?

Yes, your understanding correct.

Regarding FIFO you can refer below thread once:

(+) TMS570LS1224: ADC FIFO access - Arm-based microcontrollers forum - Arm-based microcontrollers - TI E2E support forums

And regarding memory also you are correct, the conversions storage will happen in round-robin method. First it will store the first iteration of all the configured channels in memory and then this will be followed by the second iteration of results, and this will continuous until configured memory of the corresponding group gets fill. Once group memory filled then it will start store from starting address of group again.

Sebastian Mazur said:
Specifically, is it correct to assume that if an analog value changes rapidly, the results captured in the memory would vary accordingly?

It depends on the conversion method you have chosen. If you choose single conversion mode, then all the configured channels will get conversion for one iteration only. and then we need to trigger again to do second iteration of conversion.

Whereas in continuous mode the conversion happens repeatedly until we stop the conversion forcefully.

Sebastian Mazur said:
Is it possible to somehow limit the number of results in case of reading directly from the memory?

Yes you can do it.

Refer below section in TRM to understand it:

Based on above understanding you can configure at below tab in HALCoGen:

--
Thanks & regards,
Jagadish.

0 Sebastian Mazur 5 months ago in reply to jagadish gundavarapu

Prodigy 90 points

My settings are as follows:

ADC1
Group1
Channel 9
Single conversion mode
Reading directly from the memory (RAM)

In debug mode, I executed the conversion function only once. As a result, the same value is repeated multiple times.
I expected the value to appear only once during the first execution and to update when I executed the function a second time.