User Manual

MXi AMPLIFIER CONTROLLER BOARD REV.2
PUB06-82 Rev 1 July 17, 2007 06-82-38 MXi Amplifier Controller Board Rev.2
PORT C
PC0 Output Remote Status – Error
PC1 Input DipSw #1
PC2 Input Power Supply (Relay K1) ON Status
PC3 Input DipSw #2
PC4 Input External #1 Interlock
PC5 Output VSWR Reset Control
PC6 Output PS ON Ctl +12V out [could be 24V too]
PORT D
PD0 SPI SS Used by UART
PD1 SPI MISO Used by UART and NvPot
PD2 SPI MOSI Used by UART and NvPot
PD3 SPI SCLK Used by UART and NvPot
PD4 Input Fan#1 Status, Active Low
PD5 Input Fan#2 Status, Active Low
PD6 Input Fan#3 Status, Active Low
PD7 Input Fan#4 Status, Active Low
PORT E
PE0 SCI Transmit Data Used by LCD
PE1 SCI Receive Data Used by LCD
PE2 O/P Remote Status – Remote Mode
PE3 Input VSWR Trip Status
PE4 System Main CPU Clock – 4.9152MHz
The HC08 provides two separate serial interfaces to external components, these are the synchronous peripheral
interface (SPI) and the serial communications interface (SCI).
The SCI implements the standard three-wire serial port (Rx Data, Tx Data and Ground) that would interface to a
typical computer port. The baud is settable from 300 up to 38,400 bits per second via the LCD menus. The baud
is derived from the system oscillator clock at 4.9152MHz. This frequency is recommended by the manufacturer to
easily obtain the most common bauds.
The SPI implements a four-wire clocked serial port that has four signals, Slave Select (SS), Master Out Slave In
(MOSI), Master In Slave Out (MISO) and Serial Clock (SCLK). The HC08 is always set as the Master who
initiates all serial communications. The SPI port is used to communicate with the MAX3110 UART (U2) and the
DS1867 NovPot (U16). The HC08 will send out it data stream from the MOSI line and reads any responses from
the external (Slave) devices via the MISO line. The SCLK is a serial clock (set for around 64K baud) that
synchronizes the data transfer. The presence of this clock allows must higher data rates than the asynchronous
SCI serial protocol. The SS line is a select that enables the MAX 3110 UART when low. A second individual
select line from Port A (pin PA3) is used to select the DS1867 NovPot.
6.2 POWER SUPPLY VOLTAGE AND CURRENT MONITORING
For the following description, refer to Figure 25 (Sheet #2 of the Schematic) in the upper section of the drawing for
the power supply monitoring circuitry.