Advanced Communication Board Developer Toolkit 

ABSTRACT:  POLL2.C

POLL2.C is a polled mode SDLC\HDLC terminal program. The base address is
238 Hex and additional jumpers for the external clock are needed. To build
the program, the ACB.OBJ file must be linked from the \LIBRARY directory. The
program will terminate when the "Esc" key is typed from the keyboard. POLL2
will transmit at 4800 bps and receive at the frequency of the RxC clock input.
Please remember that this is a polled program and it does have maximum data
rate limitations. For high speed examples please refer to the DMA and
interrupt driven examples.

Cables:

For SDLC\HDLC mode, transmit, receive, Tx Clock, and Rx Clock are needed. The
program may be used in a stand alone loop-back configuration, or with another
PC with an ACB or SDLC adapter installed. For most ACB adapters use TSET or
TT for an output clock and RxC as an input clock. Please note that TSET
(Transmit Signal Element Timing) is the EIA-530 equivalent of TT, the RS-232
signal Terminal Timing. For a loop-back plug connect the Transmit signal(s)
to the receive signal(s) and the TSET (EIA-530) or TT (RS-232) signal(s) to
the RxC signal(s).

  For Loop-Back Plug:

     For Single Ended (RS-232, MIL-188/114)
	Connect Tx to Rx
	Connect TSET or TT to RxC

     For Differential Interface (RS-530, V.35, MIL-188/C, etc.)
	Connect Tx+ to	Rx+
	Connect Tx- to	Rx-
	Connect TSET+ or TT+ to RxC+
	Connect TSET- or TT- to RxC-

  Point to Point Cable:

     For Single Ended (RS-232, MIL-188/114)
	Connect Tx at point A to Rx at point B
	Connect TSET or TT at point A to RxC at point B
	Connect Tx at point B to Rx at point A
	Connect TSET or TT at point B to RxC at point A

     For Differential Interface (RS-530, V.35, MIL-188/C, etc.)
	Connect Tx+ at point A to Rx+ at point B
	Connect Tx- at point A to Rx- at point B
	Connect TSET+ or TT+ at point A to RxC+ at point B
	Connect TSET- or TT- at point A to RxC- at point B
	Connect Tx+ at point B to Rx+ at point A
	Connect Tx- at point B to Rx- at point A
	Connect TSET+ or TT+ at point B to RxC+ at point A
	Connect TSET- or TT- at point B to RxC- at point A

Dip-Switch and Jumpers:

Note: If a jumper is not listed, that jumper is not relevant to this example.

    ACB-104		ACB-II		    ACB-530
	SW1 2,3,4,8 On	    SW1 1 On		SW1 2,3,4,8 On
	E2 O		    E4 RC TC		E8 0|0000
			    (See Note 1)

    ACB-III		ACB-IV		    ACB-V
	SW2 2,3,4 On	    SW1 2,3,4 On	SW1 2,3,4 On
	E10 |00|	    E2 00||0||00	(See Note 2)
	E6  |0000|

    ACB-VI		ACB-MP		    MAXPORT
	SW1 2,3,4,8 On	    None		SW1 2,3,4,8 On
			    E7 A,B (See Note 3)	(See Note 4)

   Note 1: The ACB-II does not support TSET or TT signal(s). For this card use
	   the TxC signal(s) and set E4 to RC and TC.
   Note 2: The ACB-V can only receive clocks. To use this example you will
	   either need to modify WR11 to receive transmit and receive clocks,
	   or contact technical support for a copy of the modification to
	   allow the ACB-V to source clocks. CCITT V.35 does not specify
	   a clock output.
   Note 3: The modification listed in Note 1 is enabled on the ACB-MP by
	   setting the jumpers on E7 A,B. This is only necessary when the
	   CCITT V.35 interface is selected.
   Note 4: The ACB MAXPORT will not source a clock. To use this example you
	   will need to modify WR11 to receive transmit and receive clocks.



SDLC\HDLC Note:

This program will send each character typed on the keyboard as a HDLC\SDLC
frame. All receive data is stored in a buffer until a closing flag is
received. Once a closing flag is received the 16 bit CRC is stripped off and
the frame is displayed. The largest frame that this program can currently
receive is 100 bytes. This program may be modified to allow lager frames to be
received (increase MAXFRAME). You may also modify the initialization array to
only allow frames with certain address fields to be received. Presently
all address are received.


Build Dependencies:

POLL2.C
 * ACB.OBJ
 * ACB.H
 * Z8530.H

 * Denotes that files are located in the \LIBRARY directory.