3.3.35 UDDRC ZQ Control Register 0

Name: UDDRC_ZQCTL0
Offset: 0x180
Reset: 0x02000040
Property: Read/Write

Bit 3130292827262524 
 DIS_AUTO_ZQDIS_SRX_ZQCLZQ_RESISTOR_SHARED  T_ZQ_LONG_NOP[10:8] 
Access R/WR/WR/WR/WR/WR/W 
Reset 000010 
Bit 2322212019181716 
 T_ZQ_LONG_NOP[7:0] 
Access R/WR/WR/WR/WR/WR/WR/WR/W 
Reset 00000000 
Bit 15141312111098 
       T_ZQ_SHORT_NOP[9:8] 
Access R/WR/W 
Reset 00 
Bit 76543210 
 T_ZQ_SHORT_NOP[7:0] 
Access R/WR/WR/WR/WR/WR/WR/WR/W 
Reset 01000000 

Bit 31 – DIS_AUTO_ZQ

This is only present for designs supporting DDR3 or LPDDR2/LPDDR3 devices.

Programming Mode: Dynamic

ValueDescription
0 Internally generate ZQCS/MPC(ZQ calibration) commands based on ZQCTL1.t_zq_short_interval_x1024.
1 Disable UDDRC generation of ZQCS/MPC(ZQ calibration) command. Register DBGCMD.zq_calib_short can be used instead to issue ZQ calibration request from APB module.

Bit 30 – DIS_SRX_ZQCL

This is only present for designs supporting DDR3 or LPDDR2/LPDDR3 devices.

Programming Mode: Quasi-dynamic Group 2, Group 4

ValueDescription
0 Enable issuing of ZQCL/MPC(ZQ calibration) command at Self-Refresh/SR-Powerdown exit. Only applicable when run in DDR3, LPDDR2 or LPDDR3 mode.
1 Disable issuing of ZQCL/MPC(ZQ calibration) command at Self-Refresh/SR-Powerdown exit. Only applicable when run in DDR3, LPDDR2 or LPDDR3 mode.

Bit 29 – ZQ_RESISTOR_SHARED

This is only present for designs supporting DDR3 or LPDDR2/LPDDR3 devices.

Programming Mode: Static

ValueDescription
0 ZQ resistor is not shared.
1 Denotes that ZQ resistor is shared between ranks. Means ZQinit/ZQCL/ZQCS/MPC(ZQ calibration) commands are sent to one rank at a time with tZQinit/tZQCL/tZQCS/tZQCAL/tZQLAT timing met between commands so that commands to different ranks do not overlap.

Bits 26:16 – T_ZQ_LONG_NOP[10:0]

tZQoper for DDR3, tZQCL for LPDDR2/LPDDR3: Number of DFI clock cycles of NOP required after a ZQCL (ZQ calibration long)/MPC(ZQ Start) command is issued to SDRAM.

When the controller is operating in 1:2 frequency ratio mode:

DDR3: program this to tZQoper/2 and round it up to the next integer value.

LPDDR2/LPDDR3: program this to tZQCL/2 and round it up to the next integer value.

This is only present for designs supporting DDR3 or LPDDR2/LPDDR3 devices.

Unit: DFI clock cycles.

Programming Mode: Static

Bits 9:0 – T_ZQ_SHORT_NOP[9:0]

tZQCS for DDR3/DD4/LPDDR2/LPDDR3: Number of DFI clock cycles of NOP required after a ZQCS (ZQ calibration short)/MPC(ZQ Latch) command is issued to SDRAM.

When the controller is operating in 1:2 frequency ratio mode, program this to tZQCS/2 and round it up to the next integer value.

This is only present for designs supporting DDR3 or LPDDR2/LPDDR3 devices.

Unit: DFI clock cycles.

Programming Mode: Static