"r" command vs "A" for realtime data

[ol boy]

I was tracking down a weird pattern on the o"scope today trying to increase the data rate over a 900MHz Xbee module. I was getting 2 different sized replies from the MS2 unit. Both looked too small in size to be the 209 bytes of a single "A" data request. Looking at the MS serial com spec you'd expect to see x00 x07 x41 crc crc crc crc. 7 bytes big, "A" and the 4 CRC bytes. Instead I find

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x00 x07 x72 x00 x07 x00 x00 x00 x51 x48 xD7 xA3 x0E

size of 7, "r", canid of 0, table 7, 0 offset, with a sie of 81 bytes to get, 4 crc bytes.

The ECU replays back with 88 bytes of data. Then sends out

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x00 x07 x72 x00 x07 x00 xD0 x00 x01 xAE x35 xC7 xCA

size of 7, "r", canid of 0, table 7, 208 offset, size of 1 byte, 4 crc bytes.

Then I see

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x00 x02 x00 x01 x36 xDE x22 x69

as a reply.

I know the Xbee can only send a RX packet with upto 100 bytes in one RF transmission. It seems plenty capable of reading the pages from flash to compare the tune.

Just want to know your thoughts.

Thanks Ryan

[ol boy]

Forgot to add a section of the TSdebug.txt

TSserialDataXbee.txt

[jsmcortina]

'A' fetches everything. 'r 00 07' can be used to fetch just a few bytes or many for more optimal serial usage.

James

[ol boy]

Is table 7 laid out the same way the ini file shows for an A command? Same offsets and such?

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