Converting HSERIN Data to Number

[HenrikOlsson]

Hi,

I think it's "the usual" case of not treating the data the same way in both ends.

It looks to me like you are sending ASCII but you're treating the received data as binary/raw numbers.
If you send the decimal digit '1', store that in myArray[0] and later multiply that by 100 what you'll get is 4900 because 49 is the ASCII code for '1'.
To do what you want you can use ARRAYREAD with the DEC modifier or simply use the aproach you already have but "offset" the values to account for the ASCII encoding.

varResult = ((myArray[0]-48)*100) + ((myArray[1]-48)*10) + (myArray[2]-48)

Or you could subtract 48 when receiving the digits.

/Henrik.

[RossWaddell]

Hi,

I think it's "the usual" case of not treating the data the same way in both ends.

It looks to me like you are sending ASCII but you're treating the received data as binary/raw numbers.
If you send the decimal digit '1', store that in myArray[0] and later multiply that by 100 what you'll get is 4900 because 49 is the ASCII code for '1'.
To do what you want you can use ARRAYREAD with the DEC modifier or simply use the aproach you already have but "offset" the values to account for the ASCII encoding.

varResult = ((myArray[0]-48)*100) + ((myArray[1]-48)*10) + (myArray[2]-48)

Or you could subtract 48 when receiving the digits.

/Henrik.

Thanks Henrik! I'll give it a go tonight after work.

Preferably, I'd just send the output of the 8-bit ADC module on the Master chip directly to the Slave (so, 0-255) rather than converting it to ASCII in a 3-digit format (e.g. "027"), but then I can't figure out how to process that in the ISR if I'm only getting one character at a time.

[HenrikOlsson]

So why don't you? ;-)

Master:

ADResult VAR BYTE
....
....
HSEROUT [ADResult]   '1 byte

Slave:

Duty VAR WORD
HSERIN [Duty]   '1 byte

But now, if you're trying to debug this by sending te value of Duty to the PC terminal you need to use the DEC modifier so it converts the value to ASCII for display to us humans, HSEROUT [DEC Duty]

/Henrik.

[RossWaddell]

So why don't you? ;-)

Master:

ADResult VAR BYTE
....
....
HSEROUT [ADResult]   '1 byte

Slave:

Duty VAR WORD
HSERIN [Duty]   '1 byte

But now, if you're trying to debug this by sending te value of Duty to the PC terminal you need to use the DEC modifier so it converts the value to ASCII for display to us humans, HSEROUT [DEC Duty]

/Henrik.

Thanks again, Henrik. Can I still incorporate this into my ISR? For that to work, the interrupt on Rc would need to fire when 1 byte gets into the buffet, right? So, instead of an array for 3 'characters' (which on their own are 1 byte, right?) I can just grab the next byte after receiving the AdjCmdVal.

[HenrikOlsson]

Hi,
The UART RX interrupt always* fires for each byte that comes into the RX buffer, there's no way to set a "threshold" on when the interrupt fires. After all, the buffer is only two bytes deep. But yes, you could set your code up so that after proper sync, adress, command etc you grab one byte and that's it.

* Well not always but that's details details details.....

/Henrik.

[RossWaddell]

Hi,
The UART RX interrupt always* fires for each byte that comes into the RX buffer, there's no way to set a "threshold" on when the interrupt fires. After all, the buffer is only two bytes deep. But yes, you could set your code up so that after proper sync, adress, command etc you grab one byte and that's it.

* Well not always but that's details details details.....

/Henrik.

Thanks again, Henrik. Much appreciated. I'm going to try all this out tonight.

[Art]

serialbuffer byte [4]
serialbyte var byte
index var byte

…

‘ ooh looky here… a serial byte arrived
for index = 1 to 3
serialbuffer[index] = serialbuffer[index-1]
next index
serialbuffer[0] = serialbyte

Now instead of checking for the first byte in the serial string,
check for what you call the termination byte.
I don’t know what that is, so now it’s $FE.

if serialbuffer[0] = $FE then
‘ we know the bytes serialbuffer [0,1,2,3] are the desired 4 byte string in reverse
‘ unless only a partial command was received
if serialbuffer[3] = “S” then
‘ we know now that the entire four byte command was received if there was no serial error
endif
endif

[Art]

Now if you only wanted to grab say byte 2 (beginning counting from zero).

counter var byte
counter = 0

'oh looky here.. a serial byte arrived

if serialbyte = “S” then
counter = 0
else
counter = counter + 1
endif

if counter = 2 then
byteyoucareabout = serialbyte
endif

A lot of this will fall apart if another byte of the command can be the same value as the “S” or the termination character,
which is why it’s better to go something close to the first way, and check both start and end chars if they are always the same.