Chapter 9: Configuration, Design Security, and Remote System Upgrades in the Cyclone III Device Family
9–39
Configuration Features
Figure 9–17 shows the timing waveform for a PS configuration when using an
external host device as an external host.
(1)
Figure 9–17. PS Configuration Timing Waveform
tCF2ST1
tCFG
tCF2CK
nCONFIG
nSTATUS (2)
tSTATUS
tCF2ST0
tCLK
CONF_DONE (3)
t
CH tCL
tCF2CD
tST2CK
DCLK
(4)
tDH
DATA[0]
(5)
Bit 0 Bit 1 Bit 2 Bit 3
tDSU
Bit n
User I/O Tri-stated with internal pull-up resistor
INIT_DONE
User Mode
tCD2UM
Notes to Figure 9–17:
(1) The beginning of this waveform shows the device in user mode. In user mode, nCONFIG
, nSTATUS, and CONF_DONE
are at logic-high levels. When nCONFIGis pulled low, a reconfiguration cycle begins.
(2) After power-up, the Cyclone III device family holds nSTATUSlow during POR delay.
(3) After power-up, before and during configuration, CONF_DONEis low.
(4) In user mode, drive DCLKeither high or low when using the PS configuration scheme, whichever is more convenient.
When using the AS configuration scheme, DCLKis a Cyclone III device family output pin and must not be driven
externally.
(5) Do not leave the DATA[0]pin floating after configuration. Drive it high or low, whichever is more convenient.
Table 9–13 lists the PS configuration timing parameters for Cyclone III device family.
Table 9–13. PS Configuration Timing Parameters for Cyclone III Device Family (Part 1 of 2)
Symbol
tCF2CD
tCF2ST0
tCFG
Parameter
nCONFIGlow to CONF_DONElow
nCONFIGlow to nSTATUSlow
nCONFIGlow pulse width
Minimum
Maximum
500
Unit
ns
—
—
500
ns
500
45
—
ns
(1)
tSTATUS
tCF2ST1
tCF2CK
tST2CK
tDSU
nSTATUSlow pulse width
800
s
s
s
s
ns
(2)
nCONFIGhigh to nSTATUShigh
nCONFIGhigh to first rising edge on DCLK
nSTATUShigh to first rising edge of DCLK
Data setup time before rising edge on DCLK
Data hold time after rising edge on DCLK
DCLKhigh time
—
800
(1)
800
—
—
—
—
—
—
—
2
5
tDH
0
ns
tCH
3.2
ns
tCL
DCLKlow time
3.2
ns
tCLK
DCLKperiod
7.5
ns
(4)
fMAX
DCLKfrequency
—
300
100
MHz
s
—
(3)
tCD2UM
tCD2CU
CONF_DONEhigh to user mode
650
—
CONF_DONEhigh to CLKUSRenabled
4 × maximum DCLKperiod
August 2012 Altera Corporation
Cyclone III Device Handbook
Volume 1
ALTERA [ ALTERA CORPORATION ]
