Basic Instrument Functions
R&S
®
CMW500
102
User Manual 1173.9463.02 ─ 02
5.3.5.2
Board Tests
A board test verifies that a particular hardware module works properly. Depending on the
board, the R&S CMW500 may provide different types of board tests described below.
Diagnosis Test
The R&S CMW500 measures a series of selectable diagnostic voltages and checks
whether they are within the permitted range. The permitted minimum and maximum vol-
tages are stored in the EEprom of the tested board.
A diagnoses test is provided for most of the R&S CMW500 modules.
RAM Test
The R&S CMW500 tests one or more of the memories (SRAM, SSRAM, ASRAM, DDR)
on the board. Two different types of memory tests are provided.
●
For an Address Line Test, the individual address lines of the RAM are activated one
after another in order to transfer a definite number to the RAM. If the instrument can
read the transferred and stored numbers correctly after testing all address lines, the
address lines must be independent (not interconnected), as required.
●
For a Pseudorandom (RRAN) Test, the R&S CMW500 generates a pseudo-random
bit sequence (PRBS) which is first written to the RAM and then read. The R&S
CMW500 checks whether the read PRBS is equal to the generated PRBS.
An address line test is generally faster than a PRAN test. Notice that a failed address line
test does not necessarily prove that two address lines are connected; the problem may
be due to one of the other components involved in data transmission and storage.
Download Test
The R&S CMW500 loads program data into a DSP or FPGA module and verifies that the
module responds properly.
EEprom Test
The R&S CMW500 verifies that the I2C EEprom data of the board is well-formed (i.e. the
syntax is correct, the contents are logically compatible). If no access to the EEprom data
is possible, the board is not displayed in the Selftest dialog.
Setup Dialog
