Datasheet

AD9920A
Rev. B | Page 105 of 112
Address
Data
Bits
Default
Value
Update
Type Name Description
0xBA [27:0] 0 UNUSED Do not access, or write to 0x00.
0xBB [27:0] 0 UNUSED Do not access, or write to 0x00.
0xBC [27:0] 0 UNUSED Do not access, or write to 0x00.
0xBD [27:0] 0 UNUSED Do not access, or write to 0x00.
0xBE [27:0] 0 UNUSED Do not access, or write to 0x00.
0xBF [27:0] 0 UNUSED Do not access, or write to 0x00.
Table 61. Extra Registers
Address Data Bits Default Value Update Name Description
0xC0 [27:0] 0 VD Test Do not access, or write to 0x00.
0xC1 [27:0] 0 VD Test Do not access, or write to 0x00.
0xC2 [27:0] 0 VD Test Do not access, or write to 0x00.
0xC3 [7:0] 0 SCK GPO_MASK_HIGH 1 = masks GPO[x] to high. Takes priority over normal operation.
[15:8] 0 GPO_MASK_LOW
1 = masks GPO[x] to low. Takes priority over normal operation and
GPO_MASK_HIGH.
0xC4 [27:0] 0 VD Test Test register. Do not access, or set to 0.
0xC5 [27:0] 0x1516 SCK Test Test register. Do not access, or set to 0x1516.
0xC6 [27:0] 0 UNUSED Unused register. Do not access, or set to 0.
0xC7 [27:0] 0 UNUSED Unused register. Do not access, or set to 0.
0xC8 [27:0] 0 SCK Test Test register. Do not access, or set to 0.
0xC9 [27:0] 0xFFFF SCK Test Test register. Do not access, or set to 0xFFFF.
0xCA [27:0] 0 SCK Test Test register. Do not access, or set to 0.
0xCB [27:0] 0 SCK Test Test register. Do not access, or set to 0.
0xCC [27:0] 0 UNUSED Unused register. Do not access, or set to 0.
0xCD [27:0] 0 UNUSED Unused register. Do not access, or set to 0.
0xCE [27:0] 0 UNUSED Unused register. Do not access, or set to 0.
0xCF [27:0] 0 UNUSED Unused register. Do not access, or set to 0.
0xD0 [27:0] 0 SCK Test Test register. Do not access, or set to 0.
0xD1 [19:0] 0 SCK Test Test use only. Set to 0.
[20] 0 STARTUP Must be set to 1 to start the device.
0xD2 [27:0] 0 SCK Test Test register. Do not access, or set to 0.
0xD3 [27:0] 0 SCK Test Test register. Do not access, or set to 0.
0xD4 [0] 0 SCK Test Test use only. Set to 0.
[1] 0 GPO_INT_EN
1 = allow observation of internal signals at GPO1 to GPO3 outputs
(must also set SEL_GPx bits low).
Note that GPO4 to GPO8 continue to output normal GP toggles.
GPO1: internal clock.
GPO2: CLPOB.
GPO3: delayed sample clock.
[9:2] 0 Test Test use only. Set to 0.
0xD5 [27:0] 0 SCK Test Test use only. Set to 0.
0xD6 [27:0] 0xA10 SCK Test Test use only. Set to 0xA10.
0xD7 [27:0] 0 SCK Test Test use only. Set to 0.
0xD8 [27:0] 0x888 SCK DOUT_STRENGTH
Controls drive strength of data output drivers.
0x888 = normal drive strength.
0x848 = weak drive strength.
0x808 = weaker drive strength.
0xD9 [27:0] 0 SCK Test Test use only. Set to 0.
0xDA [27:0] 0 SCK Test Test use only. Set to 0.
0xDB [27:0] SCK Test Test use only. Set to 0.
0xDC [27:0] 0xF7F SCK Test Test use only. Set to 0xF7F.
0xDD [27:0] 0x14 SCK Test Test use only. Set to 0x14.