Joined: 11 July 2007
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hello I'm searching for information about the frame I have to send to the sensor when using SPI mode. Thank you for answering me.

Joined: 1 February 2006
Location: BE
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Hello

The datasheet of 90333 will be updated shortly and will give more detailed information.
In the meantime here is a description of the data format when the line /SS is low :

Case 1 : ( XYZ = 0)

1 start byte FFh ( = only send 8 CLK pulses)
2 data bytes (MSB first) Alpha
2 data bytes (MSB first) Beta
2 data bytes (MSB first) Error Code
1 SUM byte 8 LSB of the sum of the transmitted bytes


Case 1 : ( XYZ = 1)

1 start byte FFh ( = only send 8 CLK pulses)
2 data bytes (MSB first) X
2 data bytes (MSB first) Y
2 data bytes (MSB first) Z
1 SUM byte 8 LSB of the sum of the transmitted bytes

rg

JC Depoorter

Joined: 11 July 2007
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Hello
Thank you for answering me but i'm asking for the trame the master has to send to enable the sensor to respond. For example for the 90316, the master sends AAh followed by 9 FFh. Is it the same trame for the 90333? Best regards.

Joined: 1 February 2006
Location: BE
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Hello

For the 90316, the master needs to send 2 start bytes AAh & FFh. The total dataframe is 10 x 8 CLK pulses long.

For the 90333, the master needs to send 1 start byte FFh, which is equal to keeping the MOSI line high during the complete dataframe.
The total dataframe is 8 x 8 CLK pulses long.

rg

JC Depoorter

Joined: 7 May 2008
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I am looking at building the MLX90333 into a design and there are several things that are unclear from reading the datasheet:

1. Can I program the parameters listed on page 18 of the data sheet? If so, how is this done -- there does not appear to be an explanation for this on the site. I stumbled across the PTC04 programmer -- must this be used? Do I have to buy a piece of hardware to program every part?

2. What protocol is used to obtain the readings from the sensor? Is the SS line just lowered and then the data is shifted to the uP (in other words, the MOSI line is really just a slave-to-master line in spite of the name)?

This part fits my application, but I'm having a devil of a time reading this data sheet and figuring out how to talk to the MLX90333...

Steve

Joined: 1 February 2006
Location: BE
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Hello

“The programming steps do not require any dedicated pins. The operation is done using the supply and output nodes of the IC. The programming of the MLX90333 is handled at both engineering lab and production line levels by the Melexis Programming Unit PTC-04 with the MLX90316 daughterboard and dedicated software tools (DLL - User Interface)." (Pag 12 of datahseet)

1) Yes, MLX90333 End-User Programmable Items means that all these parameters can be programmed by using the PTC-04.
Melexis only supports programming the MLX90333 through the programmer PTC-04 and you will need to buy this equipment. Please contact your local rep for additional information and pricing.

2) The SPI protocol is shown in pag 33 and the 90333 can actually operate only as a slave. If the SS line is low, the 90333 will listen for a request from the master ( MOSI = Master Out Slave In) and the slave or 90333 will answer through MISO ( Master In Slave Out). The SPI protocol for 90333 uses 3 wires, so Mosi/Miso are is done through the same wire.

Hope this helps to understand the programming of 90333.


Rg

JC Depoorter