SEROUT/SERIN problems
noobydoob
Posts: 14
I am sending serial data from BSP2px to another host controller (Raspberry Pi) via CP2104: http://www.pololu.com/product/1308.
Since CP2104 uses 3.3V, I have a logic level converter on the TX and RX lines: http://www.adafruit.com/products/395. Naturally, the BS2 lines are on the B side, and the RPI on the A side. Vdd (5V) from the BS2 is connected to VCCB and Vdd (3.3V) from the RPI is connected to VCCA.
Whenever I send data from RPI I get the correct data on the BS2, but when the BS2 transmits, the RPI gets the correct character every 3 times.
I start by sending "X" from the RPI, and the BS2 gets this correctly. Then I do SEROUT on the BS2 and send "Y" to the RPI.
The RPI gets either:
1) "Y" (which is correct)
2) The character that was sent from RPI originally, the "X". LOL?
3) "\xbe", whatever that is.
Do I need a pull-up or pull-down resistor somewhere on the CP2104 or the TX or RX lines? Or am I doing something else wrong.
Since CP2104 uses 3.3V, I have a logic level converter on the TX and RX lines: http://www.adafruit.com/products/395. Naturally, the BS2 lines are on the B side, and the RPI on the A side. Vdd (5V) from the BS2 is connected to VCCB and Vdd (3.3V) from the RPI is connected to VCCA.
Whenever I send data from RPI I get the correct data on the BS2, but when the BS2 transmits, the RPI gets the correct character every 3 times.
I start by sending "X" from the RPI, and the BS2 gets this correctly. Then I do SEROUT on the BS2 and send "Y" to the RPI.
The RPI gets either:
1) "Y" (which is correct)
2) The character that was sent from RPI originally, the "X". LOL?
3) "\xbe", whatever that is.
Do I need a pull-up or pull-down resistor somewhere on the CP2104 or the TX or RX lines? Or am I doing something else wrong.
Comments
The logic level converter is built specifically for this kind of thing, is this not strange?
any thoughts?