- /* Maybe it's a response: */
- switch(current_command) {
- case CMD_DOWNLOAD_RAW_ADC_SAMPLES_125K:
- if (UC->cmd != CMD_DOWNLOADED_RAW_ADC_SAMPLES_125K) goto unexpected_response;
- int i;
- for(i=0; i<48; i++) sample_buf[i] = UC->d.asBytes[i];
- received_command = UC->cmd;
- return;
- case CMD_DOWNLOADED_SIM_SAMPLES_125K:
- if (UC->cmd != CMD_ACK) goto unexpected_response;
- // got ACK
- received_command = UC->cmd;
- return;
- default:
- unexpected_response:
- PrintAndLog("unrecognized command %08x\n", UC->cmd);
- break;
- }
+
+ storeCommand(UC);
+
+}
+
+/**
+ * @brief This method should be called when sending a new command to the pm3. In case any old
+ * responses from previous commands are stored in the buffer, a call to this method should clear them.
+ * A better method could have been to have explicit command-ACKS, so we can know which ACK goes to which
+ * operation. Right now we'll just have to live with this.
+ */
+void clearCommandBuffer()
+{
+ //This is a very simple operation
+ cmd_tail = cmd_head;
+}
+
+/**
+ * @brief storeCommand stores a USB command in a circular buffer
+ * @param UC
+ */
+void storeCommand(UsbCommand *command)
+{
+ if( ( cmd_head+1) % CMD_BUFFER_SIZE == cmd_tail)
+ {
+ //If these two are equal, we're about to overwrite in the
+ // circular buffer.
+ PrintAndLog("WARNING: Command buffer about to overwrite command! This needs to be fixed!");
+ }
+ //Store the command at the 'head' location
+ UsbCommand* destination = &cmdBuffer[cmd_head];
+ memcpy(destination, command, sizeof(UsbCommand));
+
+ cmd_head = (cmd_head +1) % CMD_BUFFER_SIZE; //increment head and wrap
+
+}
+/**
+ * @brief getCommand gets a command from an internal circular buffer.
+ * @param response location to write command
+ * @return 1 if response was returned, 0 if nothing has been received
+ */
+int getCommand(UsbCommand* response)
+{
+ //If head == tail, there's nothing to read, or if we just got initialized
+ if(cmd_head == cmd_tail){
+ return 0;
+ }
+ //Pick out the next unread command
+ UsbCommand* last_unread = &cmdBuffer[cmd_tail];
+ memcpy(response, last_unread, sizeof(UsbCommand));
+ //Increment tail - this is a circular buffer, so modulo buffer size
+ cmd_tail = (cmd_tail +1 ) % CMD_BUFFER_SIZE;
+
+ return 1;
+