Greater buffer.

The book series by Vincent Himpe

Postby jla » Wed Dec 05, 2012 12:00 am

Is there some one who has created a greater buffer in the i2c probe.
It's now 32 characters is it possible to bult it up to 64 or higher???
Please help me.
Suc6 JLa
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i2cprobe.jpg
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Postby jla » Wed Dec 19, 2012 12:00 am

Sorry to hear that no one has this problem.
The i2c probe works fine with the EE07 probe from firm EPLUSE.com
But the max byte's to send in on cycle is three see protocol EE07 probe RH temperature probe.
When the send recieved buffer is greater i can more byte in one cycle transfered.
Im looking forward for the problem.
Thanks.
Attachments
datasheet-EE07-eng.pdf
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Specification-E2-Interface.pdf
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e2c-commando.txt
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Postby vincent_himpe » Wed Jan 23, 2013 12:00 am

the limit is in the USB protocol itself. this is a low speed device and packets cannot be longer than 63 bytes. any datastream longer than that needs to be split in two packets. the problem with that is the possibility for data corruption.

The way the probe works is that for every pacet in a packet is sent out. if you do not read the return packet in time you will corrupt the datatream.

i took 32 bytes as this is the default size of the endpoint buffer in the pic processor. i believe it is possible to change this buffer to 63 bytes.
i will check over the weekend.
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Postby vincent_himpe » Mon Feb 11, 2013 12:00 am

no luck. the total buffer size is 64 bytes.. 32 coming in and 32 going out. So this is a limit of the pic processor or compiler. i have a newer version of the compiler and will see if that can solve the problem.
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