TMS320F28335: DATA BUS VOLTAGES

Kaushik Prajapati

Part Number: TMS320F28335

Respected Sir,

I am communicating RAM using the XINTF module in the TMS320F28335.

In the below circuit-

The yellow line is DATABUS and the BLUE line is the WR command generated by the XINTF module.

My question is why the database is fluctuating during the WR command?

It should be steady during the WR.

0 Kaushik Prajapati over 3 years ago

Second Waveform-

Yellow is databus and blue is WR signal

0 tlee over 3 years ago in reply to Kaushik Prajapati

Kaushik,

It looks like there is contention on the bus. Is there only one RAM hooked up? Are you using XWE and XRD or XR/W?

Can you double-check your signal mapping between XINTF and RAM to make sure that the XWE is not connected to the RAM OE by accident?

-Tommy

0 Kaushik Prajapati over 3 years ago in reply to tlee

Yes Sir,

There are two many things on the data bus. 2 parallel ADC, 1 dual-port RAM, 2 parallel DAC, 5 Latching ICs(74HC574), 7 Octal Transceivers (74HC245).

All are sharing data-bus with 28335.

Yes sir I am using XWR, XRD, and XR/W signals.

Ok sir I will go through my circuits and software. I Will let you know If any query is generated.

Thank you

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