renga@skinner (Renga Sundara rajan) (03/01/90)
Any one who has experience with Levco's Link-II boards and Inmos
B003 boards, please help.
We have a Levco Link-II board plugged into one of the NuBus slots
on a MAc-II. One of the 4 slots on the Link-II board has a T-800
transputer module.
We are trying to connect Link-II board to one of the 10 Inmos B003
Boards that are housed in Inmos B201-1 card cage.
[Aside: Each of the B003 boards has 4 T-800 transputers whose
links 2 and 3 are used to connect them in a ring and the other
8 links (0 and 1 of the 4 T-800s) are taken to the edge connector.
The link speed on the B003 boards is set to 10 MB/sec.]
We tried the following methods.
1. Connect one of the external connector slots on the Link-II board
to one of the links on the B003 board.
We did not try to convert from
differential voltages to TTL signals but faked it as follows.
Link-II side B003 side
Link Out+ Link In
Link In+ Link Out
Link Out- not connected
Link In-
and Ground Ground
Then we tried to program the C004 switch on the Link-II board
by making the PBControl call (call to the Link-II driver)
as per the Levco Toolset documentation. (BTW, the printed
documentation differs from the Hypercard reference
stack which is not up-to-date.)
We are able to program the C004 switch
so as to connect any 2 of the 4 links of the T-800 module
which is plugged into the Link-II board and compile and
execute programs that use these connections.
We are also, apparently, able to program the C004 switch
so as to connect one of the off-board connectors to one
of the links of the resident T-800 module as long as
either nothing is plugged into the off-board connectors
or the B003 side of the connecting wire is left hanging.
If we do connect B003 and the Link-II, then the call to
PBcontrol to program the C004 switch does not return and the
system hangs. It does not matter whether the B003 box is
powered on or not. The connecting wire is a pair of twisted
wires, about 4' long.
What is happening?
2. Since the first method did not work, we connected one of the
links of an empty slot in the Link-II board to one of the
links on a B003 board. Specifically, we connected pin sockets
16 (Link Out 3), 15 (Link In 3) and 14 (Ground) of slot 2
on the Link-II board to LinkOutT0L0, LinkInT0L0 and Ground
respectively of the B003 board.
With this connection, we are able (apparently) to program
the C004 switch (the PBcontrol call returns with err set to 0).
Our understanding of the B003 board is that, when powered on
each transputer waits for bootstraping code on one of their links
and after receiving that code would not receive any messages
on any links unless some process does a receive. Our bootstraping
program simply receives a character on Link0in and then echos it
on Link0out. When compiled and linked with Levco's port of
Logical systems' TCX, TLnk and TCnv, we get a loadable module
whose first word is the # of bytes of the code to follow.
We first downloaded a program to the T-800 module on the Link-II
board (using its link 0). When it starts executing, it asks for
the name of the program to be downloaded to the B003 board. It
then reads in that file byte by byte and tries to send it to
B003 via link 1. (Link 1 of the T-800 module is connected
to link 3 of module 2 (which is connected to B003's link 0).
At this stage nothing happens. The B003 either is not getting
the byte stream or some thing more is to be done to bootstrap it.
I am at my wit's end and would **GREATLY APPRECIATE** any help
whatsoever.
Renga
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Renga Sundararajan Department of Computer Science
University of Oregon Eugene, OR 97403-1202
INTERNET: renga@cs.uoregon.edu CSNET: renga@uoregon.csnet
USENET: {decvax, allegra}!tektronix!uoregon!renga
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Renga Sundararajan Department of Computer Science
University of Oregon Eugene, OR 97403-1202
INTERNET: renga@cs.uoregon.edu CSNET: renga@uoregon.csnet