Sundance Spas SMT370v2, User Manual

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Version 1.0 Page 36 of 44 SMT370v2 User Manual
Register 0xE – DAC Register Read back.
By sending this control word, the FPGA reads back the DAC register from the AD9777. Once this
control word has been sent on CP3 of the 370, expect to receive 15 CommPort word in return on the
same link. They all start by 0xAD9777. The two last digits (LSBs) give the value of the DAC internal
register. The 370 starts by sending out register at address 0x0, and carries on up to register 0xd.
Example:
Let’s consider that the following registers have been loaded into the DAC
Register0 = 0x00010203
Register1 = 0x01111213
Register2 = 0x02212223
Register3 = 0x03313233
Register4 = 0x04414243
After sending the word 0xE0000000, the SMT370 will get back in return the following
values:
0xAD9777 01 , 0xAD9777 02 , 0xAD9777 03 , 0xAD9777 11 , 0xAD9777 12 , 0xAD9777 13 ,
0xAD9777 21 , 0xAD9777 22 , 0xAD9777 23 , 0xAD9777 31 , 0xAD9777 32 , 0xAD9777 33 , 0xAD9777 41 ,
0xAD9777 42 , 0xAD9777 43 .
This function gives the user a way to verify that the DAC has been loaded with the correct registers.
Bit
number
Description
Bit 31 1
Bit 30 1
Bit 29 1
Bit 28 0
Bit 27-0 Not Used.