uniphy Phyaction 740 Series, Информация о сервисе

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Service Information Phyaction 740 & 790-series Page 28
5 Program storage test. By means of a checksum test on the first 32k the data integrity of the
program stored in EPROM is tested. In case of a failure the buzzer will be activated 6 times
(
ERROR 21 ).
With the above tests the operation of the microcontroller is tested.
PERIPHERAL TEST
1
Bank switch circuit. The controller will switch on all banks of the EPROM one by one and check a
known value in every bank. Incase of a failure the buzzer will be activated 8 times (
ERROR 28 ).
2 LCD display. The controller checks if communications with the display controller can be activated.
Incase of a failure the buzzer will be activated 11 times fast (
ERROR 41 ).
3 I
2
C-bus. The controller checks whether all ICs connected to the I
2
C-bus are responding. In case of
a failure ERROR 43 , with error value the I
2
C-address of the IC that failed. The order of testing is:
ultrasound I/O (U6, address 4Ah), front panel I/O (U101, address 46h), keyboard I/O (U400,
address 40h), front panel ADC (U102, address 96h). If the fault occurs with the first address as
error value (4Ah), this can mean that this particular IC is failing, the microcontroller is failing or the
I
2
C-link is broken.
4 Internal timers and the internal ADC. The relation between the timer outputs and the clock
frequency is tested and the internal ADC. In case of a failure
ERROR 20 , with error code 3, 4 and
5 for a failure in timer 0, 1 and 2 respectively, error code 6 when the ADC is not busy (ADC not
started) and error code 7 when the ADC is not ready (conversion takes to long).
5 8155 (I/O-expander). The RAM of the 8155, the timer and the I/O-registers are tested. In case of a
failure
ERROR 31 , with error code 0 for a failure in the RAM, 1 till 3 for the I/O-registers and 4 for
the timer.
6 8253 (timer). The 3 timers in this IC are tested, in case of a failure ERROR 32 , with error code 0, 1
and 2 for timer 0, 1 and 2 respectively.
7 A/D-convertor. An reference voltage (Vref, 2.53 V) is converted and checked against a stored
value. A conversion result below 2.39 V or above 2.63 V (ADC-values 01E9h and 021Ah) results
in
ERROR 37 , with error value the measured ADC-value.
8 Supply vo24V, +15V and -15V through a resistive network. If the summing point of the
resistive network is below 1.16 V or above 3.47 V (ADC-values 00EDh and 02C6)
ERROR 53 is
reported, with error value the measured ADC-value.
9 Reference voltage of the ultrasound and laser dosage potentiometers. The controller tests the
reference voltage of the dosage regulators with the I
2 C-ADC. If the voltage is below 3.85 V or
above 3.85 (ADC-values 03ADh and 0313h) ERROR 38 is reported, with error value the
measured ADC-value.
With the above tests the microcontroller, peripherals, analog inputs and supply voltages have been
tested
5.3.2 Test current generator and safety circuit
TEST OF THE INITIAL STATE
The following tests are performed:
1
MF-Error line check. If the MF-errorline is in error condition (safety relay switched off) ERROR 57
is reported.
2 Dosage regulator at zero, checked by means of the potentiometer switch. If not at zero ERROR 50
(check cables if the control is at 0 position).
3 Dosage regulator output signal. This should be at or close to 0 V. A voltage above 0.1 V (ADC-
value 0014h) results in
ERROR 54 , with error value the measured ADC-value.
4
Initial voltage on the voltage-to-current-converter (V/C-converter). This voltage should be between