Specifications

The Transmit Acknowledge byte for instances 1~8 is mapped in Input I:1.1

word bits 0~7. Each transmit acknowledge bit corresponds to an instance of the

transmit object. When data is sent from PLC to the RS232 serial connection, the

Input I:1.1 bit 0 (Instance 1) toggles when the data is transmitted by the CDN366.

Bit 0 toggles between 0 and 1. Instances 2~8 are setup similarly mapped to bits

1~7.

When the short string data type is used for instance 1, the Transmit Data

Size is located in Output O:1.2 word bits 0~7. The Transmit Data Size indicates

the number of ASCII data bytes to be transmitted from DeviceNet to the RS232

serial side. Enter a number in Output O:1.2, bits 0~7 to represent how many

ASCII data characters (bytes) are to be transmitted (excluding the pre and post

strings). The orders of the characters are mapped from right (least significant

byte) to left (most significant byte). For the data size number of bytes, the first

character starts word O:1.2 at bits 0~7 (see Output Memory and Output M-File

Tables of Allen Bradley 1747-SDN).

When sending data using the Transmit Toggle and Transmit Acknowledge

(bit 0 for Tx Instance 1) the following steps should be performed.

1) The initial setting for Transmit Toggle Output word O:1.1, bit 0 is 0. In

order to send ASCII data out to the RS232 serial connection, the Transmit

Toggle bit 0 must toggle from 0 to 1.

2) Specify the number of characters (bytes) to be transmitted. This transmit

data size must be entered in Output word O:1.2, bits 0~7.

3) Enter the ASCII data in the Output memory table, starting in Word O:1.1,

bits 8~15 to be transferred to RS232 side (see Output Memory and Output

M-File Tables of Allen Bradley 1747-SDN for characters arrangement).

4) The Transmit Toggle bit 0 must toggle from 0 to 1 to transmit data for Tx

Instance 1. The PLC ladder logic program must toggle this bit.

5) When data is transmitted to RS232, Transmit Acknowledge Input word

I:1.1, bit 0 will toggle from 0 to 1. Indicate that transmit toggle can toggle

to 0 to send new data. For numerical data (Real, Usint, etc.) there is no

length byte, only the fixed number of data-size, and data bytes follow the

handshaking bytes.

15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

I:1.1 Inst. 8 Inst. 7 Inst. 6 Inst. 5 Inst. 4 Inst. 3 Inst. 2 Inst. 1 Inst. 8 Inst. 7 Inst. 6 Inst. 5 Inst. 4 Inst. 3 Inst. 2 Inst. 1

15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

O:1.1 Inst. 8 Inst. 7 Inst. 6 Inst. 5 Inst. 4 Inst. 3 Inst. 2 Inst. 1 Inst. 8 Inst. 7 Inst. 6 Inst. 5 Inst. 4 Inst. 3 Inst. 2 Inst. 1

Receive Toggle bits 8~15 (1 byte) Transmit Acknolwedge bits 0~7 (1 byte)

Receive Acknowledge bits 8~15 (1 byte) Transmit Toggle bits 0~7 (1 byte)