diff --git a/I2CTeensy.cpp b/I2CTeensy.cpp
index f034724..cfa5bb1 100644
--- a/I2CTeensy.cpp
+++ b/I2CTeensy.cpp
@@ -194,6 +194,16 @@ int CSerialPort::availableInt(uint8_t n)
   }
 }
 
+int CSerialPort::availableForWriteInt(uint8_t n)
+{
+  switch (n) {
+    case 3U:
+      return Serial3.availableForWrite();
+    default:
+      return false;
+  }
+}
+
 uint8_t CSerialPort::readInt(uint8_t n)
 {
   switch (n) {
diff --git a/IOSTM.cpp b/IOSTM.cpp
index e76fd65..1b32560 100644
--- a/IOSTM.cpp
+++ b/IOSTM.cpp
@@ -433,6 +433,7 @@ DMR      PC6    output
 YSF      PC7    output
 P25      PC8    output
 NXDN     PC9    output
+POCSAG   PA8    output
 
 RX       PA0    analog input
 RSSI     PA7    analog input
@@ -465,9 +466,9 @@ EXT_CLK  PA15   input
 #define PORT_NXDN         GPIOC
 #define RCC_Per_NXDN      RCC_AHB1Periph_GPIOC
 
-#define PIN_POCSAG        GPIO_Pin_12
-#define PORT_POCSAG       GPIOB
-#define RCC_Per_POCSAG    RCC_AHB1Periph_GPIOB
+#define PIN_POCSAG        GPIO_Pin_8
+#define PORT_POCSAG       GPIOA
+#define RCC_Per_POCSAG    RCC_AHB1Periph_GPIOA
 
 #define PIN_DSTAR         GPIO_Pin_15
 #define PORT_DSTAR        GPIOB
diff --git a/MMDVM.cpp b/MMDVM.cpp
index 639a068..6fd894c 100644
--- a/MMDVM.cpp
+++ b/MMDVM.cpp
@@ -102,7 +102,7 @@ void loop()
   if (m_nxdnEnable && m_modemState == STATE_NXDN)
     nxdnTX.process();
 
-  if (m_pocsagEnable && m_modemState == STATE_POCSAG)
+  if (m_pocsagEnable && (m_modemState == STATE_POCSAG || pocsagTX.busy()))
     pocsagTX.process();
 
   if (m_modemState == STATE_DSTARCAL)
diff --git a/MMDVM.ino b/MMDVM.ino
index ff317eb..ff392e1 100644
--- a/MMDVM.ino
+++ b/MMDVM.ino
@@ -99,7 +99,7 @@ void loop()
   if (m_nxdnEnable && m_modemState == STATE_NXDN)
     nxdnTX.process();
 
-  if (m_pocsagEnable && m_modemState == STATE_POCSAG)
+  if (m_pocsagEnable && (m_modemState == STATE_POCSAG || pocsagTX.busy()))
     pocsagTX.process();
 
   if (m_modemState == STATE_DSTARCAL)
diff --git a/POCSAGTX.cpp b/POCSAGTX.cpp
index 8306410..d53f9b7 100644
--- a/POCSAGTX.cpp
+++ b/POCSAGTX.cpp
@@ -87,6 +87,14 @@ void CPOCSAGTX::process()
   }
 }
 
+bool CPOCSAGTX::busy()
+{
+  if (m_poLen > 0U || m_buffer.getData() > 0U)
+    return true;
+  else
+    return false;
+}
+
 uint8_t CPOCSAGTX::writeData(const uint8_t* data, uint8_t length)
 {
   if (length != POCSAG_FRAME_LENGTH_BYTES)
diff --git a/POCSAGTX.h b/POCSAGTX.h
index ea41b7f..8cd75f7 100644
--- a/POCSAGTX.h
+++ b/POCSAGTX.h
@@ -35,6 +35,8 @@ public:
 
   uint8_t getSpace() const;
 
+  bool busy();
+
 private:
   CSerialRB            m_buffer;
   arm_fir_instance_q15 m_modFilter;
diff --git a/SerialRB.h b/SerialRB.h
index 4378cc9..22667d5 100644
--- a/SerialRB.h
+++ b/SerialRB.h
@@ -32,7 +32,7 @@ Boston, MA  02110-1301, USA.
 #include <Arduino.h>
 #endif
 
-const uint16_t SERIAL_RINGBUFFER_SIZE = 2000U;
+const uint16_t SERIAL_RINGBUFFER_SIZE = 1000U;
 
 class CSerialRB {
 public: