Rockwell Automation 1771-DB BASIC MODULE - Manual (Page 76)

Chapter
Programming Block-Transfers 5
5 -2
The BASIC module communicates with any PLC processor that has
block-transfer capability. Your ladder logic program and BASIC program
work together to enable proper communications between the BASIC
module and PLC processor. The BASIC module can perform both block
and discrete transfers. Use JW5 (page 1 -7) to set the BASIC module
backplane configuration. With JW5 set to 8-point mode, the BASIC
module uses 8 bits in both the input and output image table for block
transfer. When you have JW5 configured for 16-point mode the firmware
also allows you to examine bits 10–17 for handshaking.
13 00 01 02 03 04 05 06 07 10 11 12 14 15 16 17
Handshaking Bits Block Transfer Bits
Upper (10–17)
Used only in 16 point mode Lower (00–07)
Always used
Output Image Table
Output Image Table Bit Description Used with CALL
①
00–07 Do not use–Reserved for Block Transfers –
10 Reserved –
11 PRT1 BTW Req 34 (PRT1)
12 DF1 BTR Req 122
13 PRT2/DF1 BTW Req 34 (PRT2)
123
14 DH-485 READ Req 49
15 DH-485 WRITE Req 50
16 Module Interrupt Req 32
17 Reserved –
①
See Chapter 12 and 13 for information on these calls.
Data Tables