Arm Enterprises GP4020 User Manual
21: Timing Characteristics
194
GP4020 GPS Baseband Processor Design Manual
SDATA
NSOE
NSWE
NSCS
SADDR
BuILD_CLK
Taddrh
Tncs
Tnoe
Taddr
Tncsh
Tdih
Tnoeh
Tdisu
Figure 21.2 MPC Timing Diagram - External Memory Read Cycle
Note: These MPC Write and Read transactions are the same whether the ARM7TDMI core or the DMA
Controller is the current bus master.
Parameter
Min
Max
Unit
Description and notes
Tsclk
14.0
ns
B
µ
ILD Clk low period
Tsclkh
14.0
ns
B
µ
ILD Clk high period
Taddr
12.2
31.5
ns
B
µ
ILD Clk to Address Valid
Taddrh
10.7
28.0
ns
Address hold after Sclk
Tncs
11.6
30.0
ns
B
µ
ILD Clk to chip select valid
Tncsh
10.5
27.6
ns
Chip select hold after Sclk
Tnoe
13.1
33.0
ns
B
µ
ILD Clk to output enable active
Tnoeh
10.7
27.7
ns
Output enable hold after Sclk
Tnwe
9.4
24.4
ns
B
µ
ILD Clk to Write enable
Tnweh
9.9
26.0
ns
Write enable hold after Sclk
Tdisu
-2.0
-
ns
Data setup before Sclk
Tdih
7.5
-
ns
Data input hold time
Tde
9.5
30
ns
Data enable time after Sclk
Tdo
12.8
31.6
ns
Data valid time after Sclk
Tdz
11.4
29.3
ns
Data disable time after Sclk
Tdoh
10.8
28.4
ns
Data out hold time after Sclk
Table 21.1 Simulated Timing parameters for MPC External Transactions with on-chip Wait-state control
Notes:
1) MIN results simulated for -40
°C, fast silicon process, Vdd = +3.6V, output loading = 50pF (except Tdisu and
Tdih).
2) MAX results simulated for +85
°C, slow silicon process, Vdd = +3.0 V, output loading = 50pF.
3) Tnweh (NSWE rising) will ALWAYS precede Taddrh and Tncsh.