I previously gave a set of sketch code for the VFO or QRP to control the PA, to switch it from RX to TX and set the LPF to a band, 40, 30. 20m. The control signals are carried on two wires of a 4-way jack. The two control bits were connected to Arduino pins 12 & 13. But these pins, I realise are used in the QRP for TX & RX switching and so cannot be used for PA control. So I have changed to A0 & A1 pins.
This has meant a change also to the GPS sketches so the TX and RX serial data is read from these pins.
So the new code is as described below:
Caprice System
The Caprice system uses a 4 wire bus to supply power and signals. These are carried on a 4-way 3.5mm jack. The signals connect to Arduino A0 & A1.
Jack Power/Signal Socket Wire
Body GND Brown (B)
Ring PIN A1 Yellow (Y)
Ring PIN A0 Orange (O)
Tip 5V OUT Red (R)
OLED Power/Signal Wire
GND Black (K)
VDD Brown (B)
SCK Red (R)
SDA Orange (O)
PA Connections (top)
OLED
________________
o o o o o o o o |
O R B K
SDA VDD
SCK GND
Jack
o o o o o o o o |
Y O R B - -
A1 5V 12V
A0 GND GND
Outputs from GPS
A GPS uses the following connections:
GND
A0 - RX from GPS
A1 - TX to GPS
5V
Output from sketches
In the Caprice system sketches use the following connections:
GND
A0 - LSB of command (was 12)
A1 - MSB of command (was 13)
5V out
The output signals encode the signals to set the PA into one of 4 modes (0, 1, 2 & 3):
// modes, 00, 01, 10, 11 on A1, A0
#define RX 0
#define TX40 1
#define TX30 2
#define TX20 3
// SETUP
// include in setup...
// jack PA control outputs
pinMode(A0, OUTPUT);
pinMode(A1, OUTPUT);
// init band, RX
setPA(TX40); // mode 40m, set PA LPF
setPA(RX); // back to mode RX
This function outputs the modes to the PA.
// SET PA MODE
// modes 0, 1, 2, 3 output on A1, A0, active LOW
void setPA(int m) {
// set mode
switch (m) {
case 0:
digitalWrite(A1, HIGH);
digitalWrite(A0, HIGH); // RX
break;
case 1:
digitalWrite(A1, HIGH);
digitalWrite(A0, LOW); // TX40
break;
case 2:
digitalWrite(A1, LOW);
digitalWrite(A0, HIGH); // TX30
break;
case 3:
digitalWrite(A1, LOW);
digitalWrite(A0, LOW); // TX20
break;
}
}
Relay wiring
o------- 40m
in/Out---o/ /B6
o-----|
|----------|
| o------- 30m
|---o/ /B7
o------- 20m
PA Input
The PA inputs the signals and decodes them to modes (0, 1, 2 or 3):
// CONNECTIONS
// relay outputs (active HIGH)
#define PTT 5
#define B6 6
#define B7 7
// PARAMETERS
// modes
#define RX 0
#define TX40 1
#define TX30 2
#define TX20 3
// GLOBAL VARIABLES
char disp[][4] = {"", "40m", "30m", "20m"}; // display
byte mode, band; // mode 0-3, band 1-3
SETUP includes
pinMode(A0, INPUT_PULLUP); // bus LSB
pinMode(A1, INPUT_PULLUP); // bus MSB
pinMode(PTT, OUTPUT); // T/R relay
pinMode(B6, OUTPUT); // BAND 6
pinMode(B7, OUTPUT); // BAND 7
// init 40m RX
swPA(TX40); // mode 40m, set LPF
swPA(RX); // back to mode RX
The mode input is read from A1 & A0
// read mode input
mode = getMode(digitalRead(A1), digitalRead(A0)); // read 0000 00xx
/ GET MODE
// A1 & A0 gets mode, returns 0-3 (RX-TX20)
byte getMode(bool b1, bool b0) {
if (b1 == HIGH && b0 == HIGH) return RX; // 0 RX
if (b1 == HIGH && b0 == LOW) return TX40; // 1 TX 40m
if (b1 == LOW && b0 == HIGH) return TX30; // 2 TX 30m
if (b1 == LOW && b0 == LOW) return TX20; // 3 TX 20m
}
The mode is used to switch the TX/TX PTT relay (Antenna to PA or RX) and the LPF relays.
// SWITCH PA
// set PTT & LPF relays (HIGH = on), set band
void swPA(byte m) {
// first check RX or TX
if (m == RX)
digitalWrite(PTT, LOW); // RX
else {
digitalWrite(PTT, HIGH); // TX
// chose LPF freq
switch (m) {
case TX40:
digitalWrite(B6, LOW); // 40m
digitalWrite(B7, LOW);
break;
case TX30:
digitalWrite(B6, HIGH); // 30m
digitalWrite(B7, LOW);
break;
case TX20:
digitalWrite(B6, HIGH); // 20m
digitalWrite(B7, HIGH);
break;
}
band = m; // set band 1-3 for display
}
}
The PA display shows UL Band when in RX mode, and "TX" when transmitting.
// PICTURE LOOP
// Display band or "TX"
void dispUpdate() {
oled.firstPage();
do {
dispMsg(60, 0, "PA");
if (mode == RX) { // if RX
dispMsgUL(30, 15, disp[band]); // display band
dispMsgL(50, 50, "RX");
}
else {
dispMsgUL(45, 15, "TX"); // otherwise show "TX"
dispMsgL(50, 50, disp[band]);
}
} while (oled.nextPage());
}
