Evaluation Kit for CMX608/618/638
EV6180/6380
2016 CML Microsystems Plc
12
UM6180/5
6.
Detailed Description
6.1.
Hardware Description
6.1.1. Voltage Requirements
The board is equipped with three voltage regulators, which p3.3V digital, +3.3V analogue
and +1.8V digital supply voltages. The input to these regulators is provided by an ex5V
power supply. Component D3 illuminates when the +3.3V digital voltage is present on the board.
To measure the current consumption of each supply rail remove the jumper tab from the relevant
2-pin header (JP5 for +3.3V digital, JP6 for +1.8V digital, JP7 for +3.3V analogue) and connect an
ammeter to the header.
6.1.2. Clocking
The frequency of crystal X1, as supplied with the kit, is 12MHz. The crystal oscillator is disabled
when a jumper tab is fitted to JP4 and enabled when removed.
6.1.3. Device Reset
The CMX6x8 can be reset in one of three ways:
Pressing switch SW1
Issuing a C-BUS reset command via the PE0003
Driving pin 16 of connector J3 high, via the PE0003 (jumper tab must be fitted to JP2)
6.1.4. LED State Indication
LEDs D4 and D5 can be optionally connected to or disconnected from pins 19 and 20 respectively
of the CMX6x8 device. The jumper tab settings on connector J12 determine whether the LEDs are
in-circuit or not. By default both LEDs are connected in-circuit. The state of pins 19 and 20 is
controlled by the C-BUS register EXCODECCONT ($0B) and writing specific values to this register
controls the illuminated state of the LEDs when they are in-circuit. For a description of this register
refer to the CMX608/618/638 datasheet.
6.1.5. CODEC Selection
The setting of pins 5 and 6 of J12 selects an external CODEC or the internal (CMX618/638 only)
CODEC. Fitting a jumper tab to these pins will select the external CODEC option and removing
the jumper tab will select the internal CODEC option.
6.1.6. Connectors and Jumpers
The C-BUS signals from the CMX6x8 are terminated at connector J3. This is a 20-pin, right-
angled male header, which will mate with the corresponding female socket (J3 or J7) on the
PE0003 Evaluation Kit Interface Card. This allows the CMX6x8 C-BUS to be driven directly by the
PE0003.
J3 also has +3.3V digital supply and ground connections. The +3.3V supply can be connected to
pins 19 and 20 on connector J3 by fitting the jumper tab on JP3.
