Lexicon 960L Service Manual page 41

This specifies which Z80 on the card to reset. Legal Values are 0 and 1.
NumRepeats:
This optional parameter specifies how many times to run the test. A value of 0 runs the test indefinitely (until
a key is pressed). Dots are shown on the display to indicate that the test is still running.
Notes:
This test explicitly does NOT make use of the interrupt command lines (INTL, INTR).
It is assumed that the DPRAM Test, which accesses the DPRAM from the 56301 side, passes.
Z80 to 56301 Tests:
The syntax for the Z80 to 56301 Test is: Z80To56kCmdTest CardId Z80ID [NumRepeats].
Tests the Z80's ability to notify the 56301 of a command This command tests the ability of the Z80 to notify
the 56301 of a new command. The 56301 processor sends messages to the Z80s, and the Z80s send
messages to the 56301 through the DPRAM. The DPRAMs have a special feature that facilitates this; the
last two addresses of the DPRAM trigger the INT pins when written to. When address 7FE is written to from
the right (56301) side, the INTL pin goes low. If the Z80 then writes to the same address, the line returns
high. If the Z80 writes to address 7FF, the INTR pin goes low. If the 56301 then writes to the same address,
the line returns high. The Z80 writes data to address 7FF of the DPRAM driving the INTR line low. The
INTR line feeds the interrupt pins of the 56301. The test resets the Z80, then loads a tiny Z80 program into
the beginning of the DPRAM. The Z80 program writes to DPRAM address 7FF, which pulls the INTR pin of
the DPRAM low triggering an interrupt on the 56301, then halts. After loading the program into the DPRAM,
the PC releases the reset on the Z80 allowing the program to run. The PC then continuously checks a
memory location in the 56301 for a particular bit to be set indicating that a Z80 interrupt has occurred. As
soon as the PC detects the bit, it clears it, instructs the 56301 to write to address 7FF on the DPRAM to
clear the INTR pin and reports the test as passed. If the bit never goes high, the PC eventually times out
and an error is reported.
In order for this test to pass, the INTR line must be connected to the buffer feeding the interrupt pins of the
56301. The Z80 must be able to access the DPRAM memory and run programs, and the mechanism within
the DPRAM that triggers the INTR line going low must be functional for the test to pass.
Parameters:
CardID:
This number selects which reverb card to test. Legal values are 0 and 1, since only two reverb cards will be
supported. If only one card is present use the number 0.
Z80Id:
This specifies which Z80 on the card to test. Legal Values are 0 and 1.
NumRepeats:
This optional parameter specifies how many times to run the test. A value of 0 runs the test indefinitely (until
a key is pressed). Dots are shown on the display to indicate that the test is still running.
Notes:
- The following tests must pass before using this test:
- 56301DpramTest
- Z80BootTest
- Z80DpramTest
Z80 SRAM Test:
The syntax for the Z80 SRAM Test is: Z80SramTest CardId Z80ID [NumRepeats].
Tests the Z80's SRAM and the Z80's ability to access it. This command loads alternately loads two small
programs into the DPRAM for the Z80, which move data to (write) and from (read) Z80 memory space. The
test begins by filling the memory space under test with a specific data value then reading back the contents
of each memory location, confirming the data contained therein is correct. Values of 0, 0xFF, 0xAA, and
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