/**
* 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;
}
