![](http://datasheet.mmic.net.cn/200000/OR3T55-4BA256I_datasheet_15087465/OR3T55-4BA256I_86.png)
Preliminary Data Sheet, Rev. 1
ORCA Series 3 FPGAs
September 1998
86
Lucent Technologies Inc.
Configuration Data Format (continued)
Figure 52. Serial Configuration Data Format—Autoincrement Mode
Figure 53. Serial Configuration Data Format—Explicit Mode
Note: For slave parallel mode, the byte containing the preamble must be 11110010. The number of leading header dummy bits must
be (n * 8) + 4, where n is any nonnegative integer and the number of trailing dummy bits must be (n * 8), where n is any positive
integer. The number of stop bits/frame for slave parallel mode must be (x * 8), where x is a positive integer. Note also that the bit
stream generator tool supplies a bit stream that is compatible with all configuration modes, including slave parallel mode.
Table 31. Configuration Frame Format and Contents
Header
11110010
Preamble
24-bit Length Count
Configuration frame length.
11111111
Trailing header—8 bits.
ID Frame
0101 1111 1111 1111
ID frame header.
Configuration Mode
00 = autoincrement, 01 = explicit.
Reserved [41:0]
Reserved bits set to 0.
ID
20-bit part ID.
Checksum
8-bit checksum.
11111111
Eight stop bits (high) to separate frames.
Configuration
Data
Frame
(repeated for each
data frame)
01
Data frame header.
Data Bits
Number of data bits depends upon device.
Alignment Bits = 0
String of 0 bits added to bit stream to make frame header, plus
data bits reach a byte boundary.
Checksum
8-bit checksum.
11111111
Eight stop bits (high) to separate frames.
Configuration
Address
Frame
00
Address frame header.
14 Address Bits
14-bit address of location to start data storage.
Checksum
8-bit checksum.
11111111
Eight stop bits (high) to separate frames.
Postamble
00
Postamble header.
11111111 111111
Dummy address.
1111111111111111
16 stop bits.
5-5759(F)
CONFIGURATION DATA
1 0
01
PREAMBLE LENGTH
ID FRAME
CONFIGURATION
POSTAMBLE
CONFIGURATION HEADER
00
COUNT
DATA FRAME 1
DATA FRAME 2
5-5760(F)
PREAMBLE LENGTH
ID FRAME
CONFIGURATION
POSTAMBLE
CONFIGURATION HEADER
ADDRESS
00
COUNT
DATA FRAME 1
DATA FRAME 2
FRAME 2
FRAME 1
CONFIGURATION DATA
10
0 1
00