COMMANDS FOR DRIVING 
THE VHDL MODEL OF THE ROMB


ARCHITECTURE

The ROMB entity is built as a FIFO which is filled by the S-LINK LDC. When the number of words stored in the FIFO exceeds a given number, the UXOFF# signal is asserted.
The control of the FIFO reads and of the S-LINK signals, is driven by the command file named "romb_in.txt". The file "romb_out.txt" contains the interpretaton of the commands and the events that occurred on the S-LINK.

The ROMB model will check if the signals from the LDC fullfil the timing requirements of the S-LINK specification. If a violation is detected, an assertion message is generated and the violation will be logged in the file "romb_out.txt".


BASIC RULES

Spaces before and after tokens are allowed. The operation and qualifier are lower-case strings. The parameter takes one of the following formats:
<time> - VHDL-like format (space between number and unit!);
<integer dec> - integer decimal number;
<integer hex> - integer hex number;
<edge> - one of the strings : "up", "down".
<std_logic> - 0 or 1.


SPECIFICATION OF COMMANDS

GENERAL SETTINGS

The following commands can be used at the start of the simulation, they don't affect the simulation time.
 
command
qualifier
parameter
operation
set 
ds
<time>
sets data set-up time (default 10 ns)
set
dh
<time>
sets data hold time (default 1 ns)
set
es
<time>
sets LWEN# set-up time (default 10 ns)
set
eh
<time>
sets LWEN# hold time (default 1 ns)
set
width
<integer dec>
sets data width used in model (8,16,32) (default 32)
set 
depth
<integer dec>
set FIFO warning level. When the FIFO contains more words then "depth" the UXOFF# is asserted (default 4)
set
per
<time>
sets period between consecutive (multi-word) FIFO reads (default 25 ns)

PROCEDURES

Commands to test the functionality of the S-LINK LDC
command
qualifier
parameter
operation
reset 
   
performs reset operation. Waits for LDOWN# down and after for LDOWN# up. The FIFO is cleared.
take
data
<integer dec>
Reads number of words from the FIFO. The period between reads is defined by "set per" command. If the FIFO becomes empty read time is extended (until fresh data from the S-link will come). 
put
url
<integer hex>
Sets state of URL lines. Only LSB nibble is valid.
finish
   
ends simulation 

ATOMIC OPERATIONS

Commands for direct specification of stimulus signals

 
command
qualifier
parameter
operation
wait
for
<time>
suspends stimulus changes for specified time
wait
clk
<edge>
suspends stimulus till the edge of the LCLK
wait
uxoff
<edge>
suspends stimulus till the edge of the UXOFF#
assert
utdo
<std_logic>
assert UTDO#
assert
ureset
<std_logic>
assert URESET#

Piotr Kapusta - Erik van der Bij - 19 May 2000