
12-14
Lattice Semiconductor
LatticeECP/EC sysCONFIG Usage Guide
Loading the Configuration Memory
Once the PROGRAMN and INITN pins are high, configuration can begin. Depending on the configuration mode
selected, data will be accepted on either the DI or D[0:7] pins on the rising edge of CCLK. If an error occurs at any
time during transfer of the data, the INITN pin will be driven low by the LatticeECP/EC device. For handshaking
configurations, the CSN or CS1N pin can be driven high to pause configuration and stop the Master clock. The
BUSY pin can be used by the LatticeECP/EC device to pause the configuration host EC/ECP. Once the full data
stream has been shifted in a CRC calculation done during configuration will be compared to the bit stream CRC. If
they match, the device will either proceed to the Wake-up sequence or overflow the next data to the next device. If
the CRC does not match, then the INITN pin will be driven low and the device will remain in configuration mode.
Wake Up the Device
When configuration is complete, the device will wake up in a predictable fashion. The following selections deter-
mine how the device will wake up. Two synchronous wake-up processes are available. One automatically wakes
the device up when the internal Done Bit is set even if the DONE pin is held low externally. The other waits for the
DONE pin to be driven high externally before starting the wake-up process. The DONE_EX preference determines
if the synchronous wake up will be controlled by the external driving of the DONE pin or ignores the external driving
of the DONE pin.
Table 12-3 provides a list of the wake-up sequences supported by the devices.
Table 12-3. Wake-up Sequences supported by LatticeEC
Synchronous to Internal Done Bit
Sequence
Phase T0
Phase T1
Phase T2
Phase T3
Default
GOE
GSR, GWDIS
DONE
1DONE
GOE, GWDIS, GSR
2DONE
GOE, GWDIS, GSR
3DONE
GOE, GWDIS, GSR
4DONE
GOE
GWDIS, GSR
5DONE
GOE
GWDIS, GSR
6DONE
GOE
GWDIS
GSR
7DONE
GOE
GSR
GWDIS
8DONE
GOE, GWDIS, GSR
9DONE
GOE, GWDIS, GSR
10
DONE
GWDIS, GSR
GOE
11
DONE
GOE
GWDIS, GSR
12
DONE
GOE, GWDIS, GSR
13
GOE, GWDIS, GSR
DONE
14
GOE
DONE
GWDIS, GSR
15
GOE, GWDIS
DONE
GSR
16
GWDIS
DONE
GOE, GSR
17
GWDIS, GSR
DONE
GOE
18
GOE, GSR
DONE
GWDIS
19
GOE, GWDIS, GSR
DONE
20
GOE, GWDIS, GSR
DONE
21 (Default)
GOE
GWDIS, GSR
DONE
22
GOE, GWDIS
GSR
DONE
23
GWDIS
GOE, GSR
DONE
24
GWDIS, GSR
GOE
DONE
25
GOE, GSR
GWDIS
DONE