Reply To: hardware questions (speaker output)

[Michael P. Flaga]

No lower baud rate will not affect the playback of files. We are not using the software serial here. So the UART is hardware peripheral and the speed won’t affect the CPU.

Yes the Bit Rate can vary somewhat for each experience. SFE’s original demonstration was not interrupt driven and likely used on a 8MgHz PRO versus the UNO’s 16MgHz CPU and this driver is Interrupt based. Using less real time.

The speaker LEFT, RIGHT, GBUF pins  do not route the Arduino Headers. Rather they go to TWO connections; JP3 and U5. Where U5 is the typical 3.5mm stereo jack connector. JP3 is a Single In-Line Pin 0.1″ header, that is convient for soldering a connector to other speakers.

I typically use 115200 as to get a lot of debug, back and forth. Most examples use 9600 as it is very reliable. But I admit I am lazy in publishing, going back and forth. Where 115200 works fine on my UNO R3’s. That said doing the math shows 115200 is close to the 10% allowed error, so there may be some variances, between users and boards. Where I am glad you figured it out and got it working.