ST62E30B: problem with UART and transmitting bytes

hh2 · ‎2003-06-11

Posted on June 11, 2003 at 17:37

hh2 · ‎2003-06-10

Posted on June 10, 2003 at 16:40

The UART works good in receiving, but isn't possible to transmit bytes.

The transmitted charachters are not the same as I load in the UART Data register.

A simple programm without interrupts doesn't work too.

Here the simple (test-)code:

loop3: ldi uscr,003h ; 2400 Baud 8Data 2 Stopbits,

; no Interrupt at 8MHz

ldi v,100

call wait ; 100 ms

ld a,x

ld udsr,a

inc x

jp loop3

The Port PD5 (TXD) is configured as an Output PP and is initialized with a 1-Level.

Perhaps, Is there an undocumented OptionByte for the UART?

Ho can I resolve my Problem?

Helmut

henrik239955 · ‎2003-06-10

Posted on June 11, 2003 at 06:16

Hi,

The ST6230 supports inverted emission so you have to connect an external inverter on the UART output (PD5).

I hope this solves your problem...

Regards Bood

hh2 · ‎2003-06-11

Posted on June 11, 2003 at 17:37

Hi Bood,

Thank you very much. Now it works.

Helmut