SPRUJ28E November 2021 – September 2024 AM68 , AM68A , TDA4AL-Q1 , TDA4VE-Q1 , TDA4VL-Q1
The clock runs at 104 MHz: (f = 104 MHz; T = 9.615 ns).
Table 12-186 shows how to calculate timings for the GPMC using the memory parameters.
Table 12-185 shows the timing parameters (on the memory side) that determine the parameters on the GPMC side.
Figure 12-103 shows the synchronous burst write access.
AC Characteristics on the Memory Side | Description | Duration (ns) |
---|---|---|
tWC | Write cycle time | 60 |
tAVDP | nADV low time | 6 |
tWP | Write pulse width | 25 |
tWPH | Write pulse width high | 20 |
tCS | nCS setup time to nWE | 3 |
tCAS | nCS setup time to nADV | 0 |
tAVSC | nADV setup time | 3 |
For asynchronous single write access, write cycle time is WrCycleTime = WeOffTime + AccessCompletion = WeOffTime + 1. For the AccesCompletion, the GPMC requires one cycle of data hold time (nCS deassertion). For more information, see the device-specific Datasheet.
Parameter Name on GPMC Side | Formula | Duration (ns) | Number of Clock Cycles (F = 104 MHz) | GPMC Registers Configuration |
---|---|---|---|---|
ClkActivationTime | N/A (asynchronous mode) | |||
WdAccessTime | Applicable only to WAITMONITORING (the value is the same as for read access) | |||
PageBurstAccessTime | N/A (single access) | |||
WrCycleTime | WeOffTime + AccessCompletion | 57.615 | 6 | WRCYCLETIME = 0x6 |
CsOnTime | tCAS | 0 | 0 | CSONTIME = 0x0 |
CsWrOffTime | WeOffTime + 1 | 57.615 | 6 | CSWROFFTIME = 0x6 |
AdvOnTime | tAVSC | 3 | 1 | ADVONTIME = 0x1 |
AdvWrOffTime | tAVSC + tAVDP | 9 | 1 | ADVWROFFTIME = 0x1 |
WeOnTime | tCS | 3 | 1 | WEONTIME = 0x1 |
WeOffTime | tCS + tWP + tWPH | 48 | 5 | WEOFFTIME = 0x5 |