/*JSON{
"type" : "method",
"class" : "SPI",
"name" : "write",
"generate" : "jswrap_spi_write",
"params" : [
["data","JsVarArray",["One or more items to write. May be ints, strings, arrays, or objects of the form `{data: ..., count:#}`.","If the last argument is a pin, it is taken to be the NSS pin"]]
]
}
Write a character or array of characters to SPI - without reading the result back.
For maximum speeds, please pass either Strings or Typed Arrays as arguments.
*/
void jswrap_spi_write(JsVar *parent, JsVar *args) {
NOT_USED(parent);
IOEventFlags device = jsiGetDeviceFromClass(parent);
spi_sender spiSend;
spi_sender_data spiSendData;
if (!jsspiGetSendFunction(parent, &spiSend, &spiSendData))
return;
Pin nss_pin = PIN_UNDEFINED;
// If the last value is a pin, use it as the NSS pin
JsVarInt len = jsvGetArrayLength(args);
if (len>0) {
JsVar *last = jsvGetArrayItem(args, len-1); // look at the last value
if (jsvIsPin(last)) {
nss_pin = jshGetPinFromVar(last);
jsvUnLock(jsvArrayPop(args));
}
jsvUnLock(last);
}
// we're only sending (no receive)
if (DEVICE_IS_SPI(device)) jshSPISetReceive(device, false);
// assert NSS
if (nss_pin!=PIN_UNDEFINED) jshPinOutput(nss_pin, false);
// Write data
jsvIterateCallback(args, (void (*)(int, void *))spiSend, &spiSendData);
// Wait until SPI send is finished, and flush data
if (DEVICE_IS_SPI(device))
jshSPIWait(device);
// de-assert NSS
if (nss_pin!=PIN_UNDEFINED) jshPinOutput(nss_pin, true);
}
/**
* Send data through SPI.
* The data can be in a variety of formats including:
* * `numeric` - A single byte is transmitted.
* * `string` - Each character in the string is transmitted.
* * `iterable` - An iterable object is transmitted.
* \return the Received bytes (MISO). This is byte array.
*/
JsVar *jswrap_spi_send(
JsVar *parent, //!< A description of the SPI device to send data through.
JsVar *srcdata, //!< The data to send through SPI.
Pin nss_pin //!< The pin to toggle low then high (CS)
) {
// Debug
// jsiConsolePrintf("jswrap_spi_send called: parent=%j, srcdata=%j, nss_pin=%p\n", parent, srcdata, nss_pin);
NOT_USED(parent);
IOEventFlags device = jsiGetDeviceFromClass(parent);
jswrap_spi_send_data data;
if (!jsspiGetSendFunction(parent, &data.spiSend, &data.spiSendData))
return 0;
JsVar *dst = 0;
// we're sending and receiving
if (DEVICE_IS_SPI(device)) jshSPISetReceive(device, true);
// assert NSS
if (nss_pin!=PIN_UNDEFINED) jshPinOutput(nss_pin, false);
// Now that we are setup, we can send the data.
// Handle the data being a single byte value
if (jsvIsNumeric(srcdata)) {
int r = data.spiSend((unsigned char)jsvGetInteger(srcdata), &data.spiSendData);
if (r<0) r = data.spiSend(-1, &data.spiSendData);
dst = jsvNewFromInteger(r); // retrieve the byte (no send!)
}
// Handle the data being a string
else if (jsvIsString(srcdata)) {
dst = jsvNewFromEmptyString();
JsvStringIterator it;
jsvStringIteratorNew(&it, srcdata, 0);
int incount = 0, outcount = 0;
while (jsvStringIteratorHasChar(&it) && !jspIsInterrupted()) {
unsigned char in = (unsigned char)jsvStringIteratorGetChar(&it);
incount++;
int out = data.spiSend(in, &data.spiSendData);
if (out>=0) {
outcount++;
char outc = (char)out;
jsvAppendStringBuf(dst, (char*)&outc, 1);
}
jsvStringIteratorNext(&it);
}
jsvStringIteratorFree(&it);
// finally add the remaining bytes (no send!)
while (outcount < incount && !jspIsInterrupted()) {
outcount++;
unsigned char out = (unsigned char)data.spiSend(-1, &data.spiSendData);
jsvAppendStringBuf(dst, (char*)&out, 1);
}
}
// Handle the data being an iterable.
else {
int nBytes = jsvIterateCallbackCount(srcdata);
dst = jsvNewTypedArray(ARRAYBUFFERVIEW_UINT8, nBytes);
if (dst) {
data.rxAmt = data.txAmt = 0;
jsvArrayBufferIteratorNew(&data.it, dst, 0);
// Write data
jsvIterateCallback(srcdata, (void (*)(int, void *))jswrap_spi_send_cb, &data);
// Wait until SPI send is finished, and flush data
while (data.rxAmt < data.txAmt && !jspIsInterrupted())
jswrap_spi_send_cb(-1, &data);
jsvArrayBufferIteratorFree(&data.it);
}
}
// de-assert NSS
if (nss_pin!=PIN_UNDEFINED) jshPinOutput(nss_pin, true);
return dst;
}
JsVar *jswrap_spi_send(JsVar *parent, JsVar *srcdata, Pin nss_pin) {
NOT_USED(parent);
IOEventFlags device = jsiGetDeviceFromClass(parent);
jswrap_spi_send_data data;
if (!jsspiGetSendFunction(parent, &data.spiSend, &data.spiSendData))
return 0;
JsVar *dst = 0;
// we're sending and receiving
if (DEVICE_IS_SPI(device)) jshSPISetReceive(device, true);
// assert NSS
if (nss_pin!=PIN_UNDEFINED) jshPinOutput(nss_pin, false);
// send data
if (jsvIsNumeric(srcdata)) {
int r = data.spiSend((unsigned char)jsvGetInteger(srcdata), &data.spiSendData);
if (r<0) r = data.spiSend(-1, &data.spiSendData);
dst = jsvNewFromInteger(r); // retrieve the byte (no send!)
} else if (jsvIsString(srcdata)) {
dst = jsvNewFromEmptyString();
JsvStringIterator it;
jsvStringIteratorNew(&it, srcdata, 0);
int incount = 0, outcount = 0;
while (jsvStringIteratorHasChar(&it) && !jspIsInterrupted()) {
unsigned char in = (unsigned char)jsvStringIteratorGetChar(&it);
incount++;
int out = data.spiSend(in, &data.spiSendData);
if (out>=0) {
outcount++;
char outc = (char)out;
jsvAppendStringBuf(dst, (char*)&outc, 1);
}
jsvStringIteratorNext(&it);
}
jsvStringIteratorFree(&it);
// finally add the remaining bytes (no send!)
while (outcount < incount && !jspIsInterrupted()) {
outcount++;
unsigned char out = (unsigned char)data.spiSend(-1, &data.spiSendData);
jsvAppendStringBuf(dst, (char*)&out, 1);
}
} else {
int nBytes = jsvIterateCallbackCount(srcdata);
dst = jsvNewTypedArray(ARRAYBUFFERVIEW_UINT8, nBytes);
if (dst) {
data.rxAmt = data.txAmt = 0;
jsvArrayBufferIteratorNew(&data.it, dst, 0);
// Write data
jsvIterateCallback(srcdata, (void (*)(int, void *))jswrap_spi_send_cb, &data);
// Wait until SPI send is finished, and flush data
while (data.rxAmt < data.txAmt && !jspIsInterrupted())
jswrap_spi_send_cb(-1, &data);
jsvArrayBufferIteratorFree(&data.it);
}
}
// de-assert NSS
if (nss_pin!=PIN_UNDEFINED) jshPinOutput(nss_pin, true);
return dst;
}
