EDJ1104BBSE, EDJ1108BBSE, EDJ1116BBSE
Protocol Examples
Protocol Example: Read Out Predetermined Read-Calibration Pattern
Multiple reads from Multi Purpose Register, in order to do system level read timing calibration based on
predetermined and standardized pattern.
Protocol Steps:
• Precharge All
• Wait until tRP is satisfied
• MRS MR3, op-code “A2 = 1 “ and “A[1:0] = 00“
Redirect all subsequent reads into the Multi Purpose Register, and load Pre-defined pattern into MPR.
• Wait until tMRD and tMOD are satisfied (Multi Purpose Register is then ready to be read). During the period
MR3 A2 =1, no data write operation is allowed.
• Read:
A [1:0] = ‘00’ (Data burst order is fixed starting at nibble, always 00 here)
A [2] = ‘0’ (For BL8, burst order is fixed as 0,1,2,3,4,5,6,7)
A12(/BC) = 1 (use regular burst length of 8)
All other address pins (including BA [2:0] and A10(AP)): don’t care.
• After RL = AL + CL, DRAM bursts out the predefined Read Calibration Pattern.
• Memory controller repeats these calibration reads until read data capture at memory controller is optimized.
• After end of last MPR read burst wait until tMPRR is satisfied.
• MRS MR3, op-code “A2 = 0“ and “A[1:0] = valid data but value are don’t care“
All subsequent read and write accesses will be regular READs and WRITEs from/to the DRAM array.
• Wait until tMRD and tMOD are satisfied
• Continue with “regular” DRAM commands, like activate a memory bank for regular read or write access,
T0
T4 T5
T9
T17 T18 T19 T20 T21 T22 T23 T24 T25 T26 T27 T28 T29 T30 T31
T39
CK
/CK
tMRD
tMOD
1
*
Command
PALL
MRS
READ
MRS
tMPRR
NOP
tRP
NOP
NOP
NOP
tMOD
3
0
Valid
3
BA
2
*
0
0
Valid
A[1:0]
2
*
1
0
A[2]
00
Valid
Valid
Valid
00
A[9:3]
1
0
0
0
0
0
0
0
0
A10(AP)
A[11]
1
*
A12(/BC)
A[15:13]
Valid
Valid
DQS, /DQS
DQ
RL
Notes: 1. READ with BL8 either by MRS or OTF
2. Memory Control must drive 0 on A[2:0]
VIH or VIL
MPR Readout of Predefined Pattern, BL8 fixed Burst Order, Single Readout
Data Sheet E1375E50 (Ver. 5.0)
98
ELPIDA [ ELPIDA MEMORY ]
