Exatron 3000B
www.exatron.com 3-20 Chapter 3 Interface Info
BASIC HANDLER/CPU TEST CYCLE HANDSHAKE
Summary:
[EXATRON uses only standard upper case ASCII characters.]
1. HANDLER SENDS AN "H [CR]."
2. TESTER SENDS AN "R," READY.
3. HANDLER CLOSES TEST CONTACTS ONTO THE DEVICE UNDER TEST (“DUT.”)
4. HANDLER SENDS AN "S [CR]," START TEST (FIRST TEST CYCLE.)
5. TESTER SENDS TEST SORT RESULT, “1” THROUGH “8” OR "0" FOR REMOTE RETEST.
6. HANDLER OPENS TEST CONTACTS.
7. DUT
CYCLES TO AN OUTPUT TUBE; A NEW CYCLE STARTS.
SPECIAL NOTE: REMOTE FLUSH ~ The tester can send an asterisk, “✻

✻✻

✻,” (“2A” in HEX) as a handler
reset command. If the handler receives an asterisk, the test will be aborted and the device will be flushed
to the Home bin, output tube 5.
SPECIAL NOTE: REMOTE RETEST ~ You may send a zero, ���0,” to the handler as a test result. This
will cause the handler to pick up the device and replunge/retest it. A new "S" will be sent to the tester.
You may use the "0" response as many times as you wish. To end a test cycle, send the handler a "1"
through "8" as a sort command.
BASIC HANDLER/CPU TEST CYCLE HANDSHAKE
With Explanation:
1. HANDLER SENDS AN "H [CR]."
The handler establishes proper communications at the outset of every cycle (except Retest cycles.) To do
so, an "H" and a carriage return, “[CR],” are sent by the handler to the tester at the start of each test
cycle. The handler is seeking an "R," Ready, from the tester. The display will read: WAITING FOR R.
2. TESTER SENDS AN "R," READY.
3. HANDLER CLOSES TEST CONTACTS ONTO THE DEVICE UNDER TEST (“DUT.”)
If an “R” is received, the handler will close the contacts or plunge the device onto the contacts. If the
handler does not receive a response, the display will briefly read: NO RESPONSE. NO RESPONSE will
alternate with: WAITING FOR R once per second. Pressing the [Enter] button on the front panel will
cause the handler to send a new "H."
If anything other than an “R” or an “✻
✻✻
✻” is received, the handler will pause and display the message: BAD
RESPONSE. The handler will output the HEX equivalent of the actual character received by the handler
to the LEDs on the handler’s output shuttle cover. LED #1 is bit 01, LED #8 is bit 80. Pressing the [Enter]
button on the front panel will cause the handler to send a new "H" and the handler will try again to receive
an "R." Pressing the [Clear] button on the front panel will cause the handler to flush the device from the
test site and restart operation. The display will read: BIN 5 S0 FLUSH.
4. HANDLER SENDS AN "S [CR]," START TEST (FIRST TEST CYCLE.)
As stated above, once the handler receives an “R,” the test contacts will close onto the DUT. The
handler will allow time for the test contacts to close. Then the handler sends an “S [CR]” for Start Test, to
the tester. The display will read: START 1 TEST.
If you wish to abort the test at this point, press the [Clear] button. This will sort the DUT to the Home bin,
output tube 5.