SIMPLE_SERIAL
Table of Contents |
Simple Serial Object Version 1.4
Public Spin methodsStart and StopStart and Stop methods are used for starting and stopping this object. This uses/frees one cog and the rx/tx-pins used.StopCall this method after final use of object to release transmit pin.SOURCE CODE... PUB Stop
if txOkay ' if tx enabled
dira[sout]~ ' float tx pin
rxOkay := txOkay := false
Start(rxPin, txPin, baud)Call this method before first use of object to initialize pins and baud rate.
• For true mode (start bit = 0), use positive baud value. Ex: serial.init(0, 1, 9600)
For inverted mode (start bit = 1), use negative baud value. Ex: serial.init(0, 1, -9600)
• Specify -1 for "unused" rxPin or txPin if only one-way communication desired.
• Specify same value for rxPin and txPin for bi-directional communication on that pin and connect a pull-up/pull-down resistor
to that pin (depending on true/inverted mode) since pin will set it to hi-z (input) at the end of transmission to avoid
electrical conflicts. See "Same-Pin (Bi-Directional)" examples, below.
SOURCE CODE... PUB Start(rxPin, txPin, baud): Okay Stop ' clean-up if restart rxOkay := rxPin > -1 ' receiving? txOkay := txPin > -1 ' transmitting? sin := rxPin & $1F ' set rx pin sout := txPin & $1F ' set tx pin inverted := baud < 0 ' set inverted flag bitTime := clkfreq / ||baud ' calculate serial bit time return rxOkay | TxOkay Basic send/receiveHere you find basic send/receive-methods for single bytes.RxReceive a byte; blocks caller until byte received.SOURCE CODE... PUB Rx: rxByte | t
if rxOkay
dira[sin]~ ' make rx pin an input
waitpeq(inverted & |< sin, |< sin, 0) ' wait for start bit
t := cnt + bitTime >> 1 ' sync + 1/2 bit
repeat 8
waitcnt(t += bitTime) ' wait for middle of bit
rxByte := ina[sin] << 7 | rxByte >> 1 ' sample bit
waitcnt(t + bitTime) ' allow for stop bit
rxByte := (rxByte ^ inverted) & $FF ' adjust for mode and strip off high bits
Tx(txByte)Transmit a byte; blocks caller until byte transmitted.SOURCE CODE... PUB Tx(txByte) | t
if txOkay
outa[sout] := !inverted ' set idle state
dira[sout]~~ ' make tx pin an output
txByte := ((txByte | $100) << 2) ^ inverted ' add stop bit, set mode
t := cnt ' sync
repeat 10 ' start + eight data bits + stop
waitcnt(t += bitTime) ' wait bit time
outa[sout] := (txByte >>= 1) & 1 ' output bit (true mode)
if sout == sin
dira[sout]~ ' release to pull-up/pull-down
Extended send/receiveHere you find extended send/receive-methods. This serial object has just one extended send-methods.You can use it for output of strings. Str(strAddr)Transmit z-string at strAddr; blocks caller until string transmitted.SOURCE CODE... PUB Str(strAddr)
if txOkay
repeat strsize(strAddr) ' for each character in string
tx(byte[strAddr++]) ' write the character
depriciatedthese Methods are depriciated and kept for backward-compabilityfinalizeSOURCE CODE... PUB finalize RETURN Stop init(rxPin, txPin, baud)SOURCE CODE... PUB init(rxPin, txPin, baud) RETURN Start(rxPin, txPin, baud) Global VARiablesSOURCE CODE... long sin, sout, inverted, bitTime, rxOkay, txOkay License┌──────────────────────────────────────────────────────────────────────────────────────┐ │ TERMS OF USE: MIT License │ ├──────────────────────────────────────────────────────────────────────────────────────┤ │Permission is hereby granted, free of charge, to any person obtaining a copy of this │ │software and associated documentation files (the "Software"), to deal in the Software │ │without restriction, including without limitation the rights to use, copy, modify, │ │merge, publish, distribute, sublicense, and/or sell copies of the Software, and to │ │permit persons to whom the Software is furnished to do so, subject to the following │ │conditions: │ │ │ │The above copyright notice and this permission notice shall be included in all copies │ │or substantial portions of the Software. │ │ │ │THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, │ │INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A │ │PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT │ │HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF │ │CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE │ │OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. │ └──────────────────────────────────────────────────────────────────────────────────────┘ |