Part Number: LMH1219
Hello,
Make LMH1219 board to make Eye pattern, and under test now.
But there is some issue which VEO value is not changed by cable length.
-. Read 0x28 to calculate VEO as below code, but VEO value is not changed by cable length.
-. VEO value with 75M and 1M are the same value at 3G input.
-. VEO value at 3G and 12G input are different.
Question.
-. According to LMH1219 Programming Guide, VEO (0x28) has 64 steps.
-. Does it mean 0x28 register used only 6bit [5:0]?
Regards,
Nicky
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Device ID(0xF1) : 0x80
Device Revision(0xF0) : 0x02
while(1)
{
Write(0xff, 0x05); //CableEQ/Drivers Register Page
Read(0x02, 1); //Get RATE
Write(0xff, 0x04); //CTLE/CDR Register Page
Write(0x2c, 0x32); //Set to Manual
Write(0x3e, 0x00);
Write(0x11, 0xc0); //VEO SCALE=12.5mv
Write(0x23, 0xc0); //Enable HEO/VEO Acquisition override
Write(0x24, 0x02); //Disable Fast EOM & Acquire HEO/VEO
while(Read(0x24) & 0x02 !=0); //wait for ready
Read(0x27, 1); //HEO Jitter <= 1.0-HEO/64
Read(0x28, 2); //VEO, SCALE mV <= (VEO &0x3f) * SCALE_TABLE[((SCALE>>5)&0x03)]
Write(0x23, 0x40); //Disable HEO/VEO Acquisition override
Write(0x3e, 0x00);
Write(0x11, 0xc0); //VEO SCALE=12.5mv
Write(0x24, 0xC1); //Enable Fast EOM & Start EOM counter
while(Read(0x24) & 0x01 !=0); //wait for ready
Read(0x29, 1); //SCALE(not use)
Read(0x25, 8192); //Get EYE data
}
