djsundog/circuitpython
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

esp8266/hspi: Enable duplex operation of hardware SPI

Browse Source 
Without this, spi.read(1, 0xff) would use 16 clock cycles,
first to send 0xff and then to receive one byte, as visible
with a logic analyzer.
This commit is contained in:
Radomir Dopieralski 2016-08-25 10:42:33 +02:00 committed by Paul Sokolovsky
parent 9897bcaa73
commit 891479e62a
1 changed files with 5 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
esp8266/hspi.c
View File

@ -199,7 +199,11 @@ uint32_t spi_transaction(uint8_t spi_no, uint8_t cmd_bits, uint16_t cmd_data,
// This is rather inefficient but allows for a very generic function.
// CMD ADDR and MOSI are set below to save on an extra if statement.
if (din_bits) {
SET_PERI_REG_MASK(SPI_USER(spi_no), SPI_USR_MISO);
if (dout_bits) {
SET_PERI_REG_MASK(SPI_USER(spi_no), SPI_DOUTDIN);
} else {
SET_PERI_REG_MASK(SPI_USER(spi_no), SPI_USR_MISO);
}
}
if (dummy_bits) {
SET_PERI_REG_MASK(SPI_USER(spi_no), SPI_USR_DUMMY);