EP4CE30F29C7N Datasheet, PDF (200/488 Pages) Altera Corporation – Cyclone IV Device Handbook, Volume 1

8–36
Chapter 8: Configuration and Remote System Upgrades in Cyclone IV Devices
Configuration
PS Configuration Timing
A PS configuration must meet the setup and hold timing parameters and the
maximum clock frequency. When using a microprocessor or another intelligent host
to control the PS interface, ensure that you meet these timing requirements.
Figure 8–16 shows the timing waveform for PS configuration when using an external
host device.
Figure 8–16. PS Configuration Timing Waveform ⁽¹⁾
nCONFIG
t_CF2ST1
t_CFG
t_CF2CK
nSTATUS (2)
CONF_DONE (3)
DCLK (4)
DATA[0]
t_STATUS
t_CF2ST0
t_CLK
t_CF2CD
t_CH t_CL
t_ST2CK
t_DH
Bit 0 Bit 1
t_DSU
Bit 2
Bit 3
User I/O User mode Tri-stated with internal pull-up resistor
INIT_DONE
Bit n
(5)
User Mode
t_CD2UM
Notes to Figure 8–16:
(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 nCONFIG is pulled low, a reconfiguration cycle begins.
(2) After power up, the Cyclone IV device holds nSTATUS low during POR delay.
(3) After power up, before and during configuration, CONF_DONE is low.
(4) In user mode, drive DCLK either high or low when using the PS configuration scheme, whichever is more convenient.
When using the AS configuration scheme, DCLK is a Cyclone IV device output pin and must not be driven externally.
(5) Do not leave the DATA[0]pin floating after configuration. Drive the DATA[0]pin high or low, whichever is more
convenient.
Table 8–12 lists the PS configuration timing parameters for Cyclone IV devices.
Table 8–12. PS Configuration Timing Parameters For Cyclone IV Devices (Part 1 of 2)
Symbol
Parameter
t_CF2CD
nCONFIG low to
CONF_DONE low
Minimum
Maximum
Unit
Cyclone IV ⁽¹⁾ Cyclone IV E ⁽²⁾ Cyclone IV ⁽¹⁾ Cyclone IV E ⁽²⁾
—
500
ns
t_CF2ST0
nCONFIG low to
nSTATUS low
—
500
ns
t_CFG
nCONFIG low pulse
width
500
—
ns
t_STATUS
nSTATUS low pulse
width
45
230 ⁽³⁾
µs
Cyclone IV Device Handbook,
Volume 1
May 2013 Altera Corporation