AM35x McSPI FAQ

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How can I get support?

 * Technical Support
 * Sitara E2E forums

What is TURBO mode
The turbo mode improves the throughput of the SPI interface when a single channel is enabled by allowing transfers until the shift register and the MCSPI_RXx register are full. The turbo mode is useful (time savings) when a transfer exceeds two words. This mode is programmable per channel (via the SPI1.MCSPI_CHxCONF[9] TURBO bit). When several channels are enabled, the TURBO bit has no effect.

TURBO mode can be used in TX/RX and RX only modes. TURBO mode can also be used with polling, FIFO, and DMA modes. TURBO mode can be combined with SINGLE mode.

Limitations
 * Only supports one enabled channel
 * TURBO mode does not by itself maintain CSn active between words (use SINGLE for this).

How do I keep CSn active between words?
To maintain an activce CSN between multiple words you need to set the SPI1.MCSPI_MODULECTRL[0] SINGLE bit. control of the CSn bit is now the responsibility of the software using the SPI1.MCSPI_CHxCONF[20] FORCE bit. The relationship between the FORCE bit and CSn signal is as follows:


 * – Writing 1 to the SPIm.MCSPI_CHxCONF[20] FORCE bit drives the SPIM_CSx line high when the SPIm.MCSPI_CHxCONF[6] EPOL bit is set to 0. SPIM_CSx is driven low when the SPIm.MCSPI_CHxCONF[6] EPOL bit is set to 1.
 * – Writing 0 to the SPIm.MCSPI_CHxCONF[20] FORCE bit drives the SPIM_CSx line low when the SPIm.MCSPI_CHxCONF[6] EPOL bit is set to 0. SPIM_CSx is driven high when the SPIm.MCSPI_CHxCONF[6] EPOL bit is set to 1.

Only a one channel can be enabled when using SINGLE mode.

From where can I download the BSL code for the AM3517 EVM?

 * The latest BSL code can be downloaded from the Logic Website (registration required)

I want to connect my own SPI device to the AM3517 EVM or Experimenter Board. How can I do this?
McSpi1 signals are accessible via the following connectors J25 on the application board of the AM3517 EVM: pin 6 - MCSPI1_CLK pin 5 - MCSPI1_SIMO pin 8 - MCSPI1_SOMI pin 7 - MCSPI1_CS0 J29 on the application board of the AM3517 EVM: pin 54 - MCSPI1_CLK pin 56 - MCSPI1_SIMO pin 58 - MCSPI1_SOMI pin 52 - MCSPI1_CS0 J22 (PERIPHERAL IO) on the Experimenter Board: pin 82 - MCSPI1_CLK pin 84 - MCSPI1_SOMI pin 86 - MCSPI1_SIMO pin 88 - MCSPI1_CS0 pin 90 - MCSPI1_CS1 pin 92 - MCSPI1_CS2 pin 94 - MCSPI1_CS3

McSPI2 signals are accessible via the following connectors J22 (PERIPHERAL IO) on the Experimenter Board: pin 95 - MCSPI2_CLK pin 97 - MCSPI2_SOMI pin 99 - MCSPI2_SIMO pin 100 - MCSPI2_CS0 pin 98 - MCSPI2_CS1

McSPI3 signals are accessible via the following connectors Note: MCSPI3 cannot be used with the full 24 bit video connector, 16 bit video is allowed. J29 on the application board of the AM3517 EVM: pin 53 - MCSPI3_CLK pin 55 - MCSPI3_SIMO pin 57 - MCSPI3_SOMI pin 51 - MCSPI3_CS0 J4 on the application board of the AM3517 EVM: pin 26 - MCSPI3_CLK pin 25 - MCSPI3_SIMO pin 28 - MCSPI3_SOMI pin 27 - MCSPI3_CS0 J23 (DEBUG IO) on the Experimenter Board: pin 6 - MCSPI3_CLK pin 10 - MCSPI3_SOMI pin 8 - MCSPI3_SIMO pin 12 - MCSPI3_CS0

McSPI4 signals are not accessible via any connector

Are AM3517 EVM/Experimenter Board schematics available?

 * EVM and Experimenter Board schematics can be downloaded from the Logic Website (registration required)

What is the part number for the connector on the AM3517 experimenter board?

 * To mate with J22 & J23 on the Experimenter Board - Hirose DF40C-100DP-0.4V(51) (100 PIN, .4MM PITCH, 1.5MM STACK HEIGHT )
 * To populate J29 on EVM application board - Samtec SFM-150-02-S-D-LC (SOCKET, FEMALE, 0.050IN, 100 PIN, 2X50)
 * To populate J25 on EVM application board - Molex 87831-1220 (HEADER, MALE, 0.100IN, 80PIN, 2X40)