UARTs
From Gumstix User Wiki
- Logic level (3.3V) signals
- FFUART speeds to 230 kbps (normally mapped to ttyS0 in the kernel and Y0 in some schematics )
- HWUART speeds to 921 kbps (normally mapped to ttyS3 in the kernel and Y1 in some schematics)
- Both can use RxD, TxD, RTS, CTS.
- STUART speeds to 230 kbps (normally mapped to ttyS2)
- BTUART is not an exposed interface; mapped to ttyS1 by the kernel and connected physically to the bluetooth module if one is present.
- Note! Current kernels use ttyS3 (HWUART) for bluetooth. This is available on the BTUART pins by setting GPIO42 and 43 to AF3 - and this is the default configuration. This can be very confusing if you want to use the HWUART for something else! To re-enable HWUART on ttyS3, make bluetooth use ttyS1 (see /etc/default/bluetooth) and then set GPIO42 to AF1 in and GPIO43 to AF2 out. You can then set GPIO48 to AF1 out (HWUART TXD) and GPIO49 to AF1 in (HWUART RXD).
http://docwiki.gumstix.org/Gumstix_UARTs
Contents
UARTs
FFUART
FF_CTS |
FF_RTS |
FF_TXD |
FF_RXD |
- Logic level (3.3V) signals
- Speeds to 230 kbps
- Normally mapped to ttyS0 in the kernel and Y0 in some schematics
- FFUART pins are located on the 60-pin Hirose connector
HWUART
STUART
BTUART
BT_CTS |
BT_RTS |
BT_TXD |
BT_RXD |
BT_NRESET |
- BTUART pins are located on the 60-pin Hirose and 24-pin flex ribbon connectors.
- It is not an exposed interface; mapped to ttyS1 by the kernel and connected physically to the bluetooth module if one is present.