# Multi-word slave\_spi messages require START\_TRANSFER\_IMMEDIATE

**URL:** <https://forum.uvvm.org/t/multi-word-slave-spi-messages-require-start-transfer-immediate/303>\
**Category:** Bitvis VIP SPI\
**Created:** [July 1, 2022, 10:09pm UTC](https://forum.uvvm.org/t/multi-word-slave-spi-messages-require-start-transfer-immediate/303 "2022-07-01T22:09:55Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![sdunnington](https://dub1.discourse-cdn.com/flex017/user_avatar/forum.uvvm.org/sdunnington/32/97_2.png) [@sdunnington](https://forum.uvvm.org/u/sdunnington)\
**Post date:** [July 1, 2022, 10:09pm UTC](https://forum.uvvm.org/t/multi-word-slave-spi-messages-require-start-transfer-immediate/303/1 "2022-07-01T22:09:55Z")

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Because of the looping mechanisms multi word SPI transfers require START\_TRANSFER\_IMMEDIATE to complete and move on to the second word or a break in SS\_N.  
This was misleading to me since spi\_master commands make a distinction between action\_between\_words and when\_to\_start\_transfer but spi\_slave commands do not.

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**Author:** ![Marius](https://dub1.discourse-cdn.com/flex017/user_avatar/forum.uvvm.org/marius/32/43_2.png) [@Marius](https://forum.uvvm.org/u/Marius)\
**Post date:** [July 4, 2022, 5:59pm UTC](https://forum.uvvm.org/t/multi-word-slave-spi-messages-require-start-transfer-immediate/303/2 "2022-07-04T17:59:47Z")

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Hi,  
Yes, as you have stated the multi-word SPI slave require that the `when_to_start_transfer` is set to `START_TRANSFER_IMMEDIATE`. I belive this could be clarified in the documentation - thank you for reporting 😃

Br,  
Marius