SPRUI30H November 2015 – May 2024 DRA745 , DRA746 , DRA750 , DRA756
This section lists all the formulas to calculate asynchronous NOR timing parameters. This is the case when GPMC_CONFIG1_i[11:10] DEVICETYPE = 0x0 and when READTYPE or WRITETYPE are set to asynchronous mode. Table 15-459 describes the asynchronous NOR formulas.
Configuration Parameter | Unit | Description |
---|---|---|
A | ns | Pulse duration – gpmc_cs low |
B | ns | Delay time – gpmc_cs valid to gpmc_advn_ale invalid |
C | ns | Delay time – gpmc_cs valid to gpmc_oen_ren invalid (single read) |
D | ns | Pulse duration – address bus valid - 2nd, 3rd and 4th accesses |
E | ns | Delay time – gpmc_cs valid to gpmc_wen valid |
F | ns | Delay time – gpmc_cs valid to gpmc_wen invalid |
G | ns | Address invalid duration between two successive R/W accesses |
H | ns | Setup time – read data valid before gpmc_oen_ren high |
I | ns | Delay time – gpmc_cs valid to gpmc_oen_ren invalid (burst read) |
J | ns | Delay time – address bus valid to gpmc_cs valid |
Delay time – data bus valid to gpmc_cs valid | ||
Delay time – gpmc_ben0/gpmc_ben1 valid to gpmc_cs valid | ||
K | ns | Delay time – gpmc_cs valid to gpmc_advn_ale valid |
L | ns | Delay time – gpmc_cs valid to gpmc_oen_ren valid |
M | ns | Delay time – gpmc_cs valid to first data latching edge |
N | ns | Pulse duration – gpmc_ben0/gpmc_ben1 valid time |
O | ns | Delay time – gpmc_cs valid to gpmc_advn_ale valid |
The configuration parameters are calculated through the following formulas. These formulas are not exhaustive. For more information, see the device data manual.
Figure 15-99 shows a simplified example of an asynchronous NOR single write where formulas are associated with signal waves.
Write multiple access is not supported in asynchronous mode. If WRITEMULTIPLE is enabled with WRITETYPE as asynchronous, the GPMC processes single asynchronous accesses.