NCR 7870 manual Examples of Host Access to Tallies

7-64 Chapter 7: Programming

Host Access to Tallies

The host can send Long Format Codes, Short Format Codes, RS-232 Format Codes, and IBM 4683 Format Codes to read the scanner tallies. The following table shows the Long Format Codes and the RS-232 Format Codes to use.

Tally	Long Format Codes: OCIA and Single-Cable	RS-232 Codes
	Scanner/Scale OCIA
C1	00H, 33H, 3DH, 32H, 31H	33H, 3dH, 32H, 31H
C2	00H, 33H, 3DH, 32H, 32H	33H, 3dH, 32H, 32H
C3	00H, 33H, 3DH, 32H, 33H	33H, 3dH, 32H, 33H
C4	00H, 33H, 3DH, 32H, 34H	33H, 3dH, 32H, 34H
C5	00H, 33H, 3DH, 32H, 35H	33H, 3dH, 32H, 35H

Note: Parity, BCC, and so on, appropriate to the communication protocol must be added.

Examples of Host Access to Tallies

Example 1

Host requesting tally C3 through single-cable OCIA.

30H b3H 3dH 32H b3H

8fH

The NCR 7870 response to the host request.

30H 33H 3yH 3xH 3xH 3xH 3xH 3xH 3xH 3xH

BCC (with EOM Bit)

x = Decimal digit with high order digit sent first
y = Tally count number
BCC = Block Check Character - an exclusive OR of all previous bytes
Presence of BCC specified by protocol	16823