/************************GET_UDDS_BUFFERS ***********************************

This module will transfer eight 320 byte DS310 frames into memory provided

the DIO-32F is configured as follows:

1) All ports mode 0 (NON LATCHED).

2) PORT A for read. (samples DS310 8 bit data).

3) PORT C for write. (used to control DS310 transport).

4) PORT D for read. (used to sense DS310 transport status).

A DB25 male to 50-pin female edge connector cable with the following pin outs

is attached:

DS310 TO DIO-32F INTERFACE CABLE

DS310 DIO-32F

SIGNAL PIN # SIGNAL PIN #

READ 17 OUT1 1

SR 02 OUT2 22

BUSY 03 IN1 29

DR 01 ACK1 27

D1 04 DIOA0 37

D2 05 DIOA1 39

D3 06 DIOA2 38

D4 07 DIOA3 40

D5 08 DIOA4 35

D6 09 DIOA5 42

D7 10 DIOA6 36

D8 14 DIOA7 41

ON LINE 18 DIOD0 04

DATA VALID 16 DIOD1 01

STOP CMD 22 DIOC0 14

START CMD 23 DIOC1 12

REWIND CMD 21 DIOC2 13

The transfer sequence follows:

1) Start a buffer

a) pulse READ

2) Perform the following 320 times to empty DS310 buffer:

a) pulse SR

b) wait for BUSY to drop

b1) if busy doesn't drop within approx 5 usecs,

then check to see if its because UDDS DATA VALID

is clear indicating EOD,

else an error of some kind has occurred.

c) if BUSY dropped then pulse DR

d) shift 1 word into "buffer"

e) repeat from step 2a 320 times.

3) repeat from step 1 eight times.

Note: This module does not check to see if the UDDS panel is online

before initiating the handshake. While offline, the UDDS panel

is in "MAINTENANCE MODE" and will provide data while disregarding

any handshake sequence. Online checking is performed in the main

routine and was omitted here so that this module could be used to

develop diagnostic procedures.

This module including handshake timing, sequence and software implementation

was developed by J. Martin, ATK.

*****************************************************************************/

GET_UDDS_BUFFERS() {

int buf_pointer = 40; /* reset buffer pointer */

/* Assemble eight 320 byte UDDS frames into mbufer */

for (frame=1; frame<=8; ++frame)

{

/* Start a buffer (pulse READ) */

outpw(cfg1, 0x0001);

outpw(cfg1, 0x0000);

for (counter=1; counter<=320; ++counter) { /* perform SR-BUSY-DR sequence */

/* 320 times */

timeout = 250000; /* typically on a 386dx/33, busy

will drop after sr before

timeout decrements 10 times.

has a large value to

allow udds buffer to empty

just after EOD */

while ((DIO32_STATUS() & 0x0800)) { /* whle BUSY is set... */

outpw(cfg2, 0x0001); /* pulse SR until BUSY is clear */

outpw(cfg2, 0x0000);

timeout--; /* should see BUSY drop < 5 usecs */

if (timeout <=0 && !DATA_VALID()) /* if not, is UDDS out of data? */

{ printf("\x1B[%d;%df",13,20);

printf(" END OF DATA detected. ");

return(0); } /* END OF DATA detected*/

else if (timeout <=0) /* UDDS has data but still no BUSY */

/* continue pulsing SR forever or */

/* until BUSY goes low. (program */

/* can hang here, power down UDDS */

/* panel to force busy low */

{ timeout = 250000;

printf("\x1B[%d;%df",13,20);

printf("UDDS not answering request for data.%s\r",TAB);}

}

/* BUSY went low */

outpw(cfg1, 0x0002); /* pulse DR */

outpw(cfg1, 0x0000);

mbufer[buf_pointer] = inp(porta); /* shift 1 byte into mbufer */

++buf_pointer; /* increment buffer pointer */

} /* end 320 byte frame */

} /* end 8 frame record */

return(1); /* END OF DATA not detected */

}/*********************** END OF GET_UDDS_BUFFER ***************************/