Transmit-B-9—
Control-B-10—
Receive-B-11—
Indication-B-12—
Signal Timing-13—
14—
15—
Figure A-2. X.21 Interface.
APPENDIX A: Interface Standards
—1-Frame Ground
—2-Transmit-A
—3-Control-A
—4-Receive-A
—5-Indication-A
—6-Signal Timing-A
—7
—8-Signal Ground
13
