Serial 16f628A works only in specific baud

[Christos]

following code ONLY works at 1200 baud, ANY other rate (tested 300,4800,9600,19200) produce trash

software serial NEVER did work

#chip 16f628A, 4
#config OSC = INTOSC
#define USART_BAUD_RATE 1200
#define SerOutPort PORTB.4
#define SerInPort PORTB.5
InitSer 1, r1200, 1 + WaitForStart, 8, 1, none, invert

DIR PortB out

SerPrint 1,"soft"
HSerPrint "hard"

[Anobium]

Are you using the latest Hot Release? If not, please upgrade.

Please let us know the results.

[Christos]

version 0.94 yes

just tried same program in microbasic pro
and works ok, so all my hardware is good and working

[Anobium]

Thanks.

We have tested and we have demonstration programs for serial, so, I need to ask a few questions.

Does Software serial or Hardware serial not work? or, both?

Does one work when only one type is programmed? ie Hardware only or Software only?

Are you communications direct to your PC terminal or via Max232 type converters?

I have just tested here on my simulator. Looks good for software and hardware. My test code is shown below.

Can you have a look the demos please? the config for software is shown in the demos.

Evan

; ----- Configuration
#chip 16f628A, 4
#config OSC = INTOSC

; ----- Define Hardware settings
  Dir PORTB.4 Out  'send on Pin 5
  Dir PORTB.5 In   'receive on Pin 7 (PCD)

  'Config Software-UART
  #define SendAHigh Set PORTB.4 ON
  #define SendALow Set PORTB.4 OFF
  #define RecAHigh PORTB.5 ON
  #define RecALow PORTB.5 OFF
  InitSer 1, r2400, 1+WaitForStart, 8, 1, None, nORMAL

  'Config hardware UART
  #define USART_BLOCKING
  #define USART_BAUD_RATE 2400

'  'Invert UART data polarity to connect without max232:
'  Set TXCKP On     'inverted transmit data polarity
'  Set RXDTP On     'inverted receive data polarity
'  Wait 100 Ms

; ----- Variables
  ' No Variables specified in this example. All byte variables are defined upon use.

; ----- Main body of program commences here.
  'Message after reset
  SerPrint 1, " PIC 16f628A"
  SerSend 1, 13  ' "Carriage Return"
  SerSend 1, 10  ' "Line Feed"

SerPrint 1,"soft"
HSerPrint "hard"

[Christos]

hi and thanx

both serial and hardware do NOT work in my program, either alone or together.

using STK500's converter (max232)

i copy paste your test and make the following conclusions
i have fully working software serial :) my mistake was
#define SerOutPort PORTB.4
it does not exist as a define i misread manual correct is
#define SendAHigh Set PORTB.4 ON
#define SendALow Set PORTB.4 OFF

HOWEVER i found the real problem in HARDWARE serial
it does trim final 2 bytes in string in low baud rates (300 -1200)
does NOT trim them at high boud rates 9600-19200 (maybe more)

[Anobium]

Ok. Good in software.

I personally use hw usart extensively at a range of different speeds - no issues. I do not think we have had any issues reported for a number of years.

Post your test code as an attachment please. Please also ensure you have the original usart.h file when you are testing.

Again, please look at the serial demos foe inspiration.

Evan

[Christos]

the following one example is helpfull i believe

#chip 16f628A, 4
#config OSC = INTOSC

  #define USART_BLOCKING
  #define USART_BAUD_RATE 300

HSerPrint "hard-"
HSerPrint "hardware"

end

above code prints "hard-hardwa"

#chip 16f628A, 4
#config OSC = INTOSC

  #define USART_BLOCKING
  #define USART_BAUD_RATE 19200

HSerPrint "hard-"
HSerPrint "hardware"

end

above AND below code prints "hard-hardware"

#chip 16f628A, 4
#config OSC = INTOSC

  #define USART_BLOCKING
  #define USART_BAUD_RATE 300

HSerPrint "hard-"
HSerPrint "hardware"

wait 100 ms
end

[Anobium]

Sorry, I cannot reproduce on the test bed here. I used you code and I got 'hard-hardware' in all cases.

I have 628a, max232 to PC/Putty terminal. PC serial driver is set to FIFO and small 16 byte buffer.

[Anobium]

A thought.

Have a look at the latest help. http://gcbasic.sourceforge.net/help/ I did update with more information on hardware serial.

The complete code would be:

~~~~~
; ----- Configuration

chip 16f628A, 4

config OSC = INTOSC

'Config hardware UART
#define USART_BLOCKING
#define USART_TX_BLOCKING
#define USART_DELAY 5 ms ' default is 1 ms
#define USART_BAUD_RATE 19200

HSerPrint "hard-"
HSerPrint "hardware"
~~~~

[Christos]

whats new is online ? its same as offline (btw it is missing define USART_DELAY what it does tweaking?)

your code is at 19200 baud and yes it print full text
altering baud to 300, problem appears

adding a "wait 100 ms" to the end prints everything

i also use putty/PC/Win7 64 but don't believe its the issue ! since following microbasic code works

program test

main:

UART1_Init(300)
UART1_Write_Text("hard-")
UART1_Write_Text("hardware")

end.

notice in asm output that the program "ends" with a sleep command
is it possible that sleeps too fast before last characters send out ?
alternative compilers end program with only a GOTO to itself
(thats also saves 1 programword :))

can somehow f.e. the sleep added ONLY if "end" in basic code added ?

[Anobium]

Re online and offline. The offline help file is the help released with the Hot Release. We maintain the Help as we add functionality and I update the online as I proceed. You can always check the Changes section - this shows the dates etc.

I did over a range of baud rates. Puzzled.

Re your code. Add a do forever-loop to the end of your code. This will prove your theory regarding end of code timing.

[Anobium]

I will add to the next release the definition of usart_delay. I had missed that one. Thank you.

[Christos]

tried a
do
loop
instead of
wait 100 ms

and yes i have all bytes at 300 baud as well

[Anobium]

Excellent. I will add some words to the Help File explaining the need to enable a wait for the usart buffer to empty before the end of the program.