Seed can implementation
Fork of SEEED_CAN by
seeed_can_spi.cpp
- Committer:
- Just4pLeisure
- Date:
- 2013-11-12
- Revision:
- 2:fd026fcfde94
- Parent:
- 0:f5d099885d3d
File content as of revision 2:fd026fcfde94:
/* seeed_can_spi.cpp * Copyright (c) 2013 Sophie Dexter * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #include "seeed_can_spi.h" /** reset the MCP2515 */ void mcpReset(mcp_can_t *obj) { obj->ncs = 0; obj->spi.write(MCP_RESET); obj->ncs = 1; wait_ms(10); } /** read from a single MCP2515 register */ uint8_t mcpRead(mcp_can_t *obj, const uint8_t address) { uint8_t result; obj->ncs = 0; obj->spi.write(MCP_READ); obj->spi.write(address); result = obj->spi.write(0x00); obj->ncs = 1; return result; } /** read multiple MCP2515 registers sequentially into an array (relies on address auto-increment) */ void mcpReadMultiple(mcp_can_t *obj, const uint8_t address, uint8_t values[], const uint8_t n) { obj->ncs = 0; obj->spi.write(MCP_READ); obj->spi.write(address); for (uint32_t i=0; i<n; i++) { values[i] = obj->spi.write(0x00); } obj->ncs = 1; } /** read the specified MCP2515 receive buffer into an array (needs one fewer SPI transfer than mcpReadMultiple) */ void mcpReadBuffer(mcp_can_t *obj, const uint8_t command, uint8_t values[], const uint8_t n) { obj->ncs = 0; obj->spi.write(command); for (uint32_t i=0; i<n; i++) { values[i] = obj->spi.write(0x00); } obj->ncs = 1; } /** write to a single MCP2515 register */ void mcpWrite(mcp_can_t *obj, const uint8_t address, const uint8_t value) { obj->ncs = 0; obj->spi.write(MCP_WRITE); obj->spi.write(address); obj->spi.write(value); obj->ncs = 1; } /** write to multiple MCP2515 registers consecutively from an array */ void mcpWriteMultiple(mcp_can_t *obj, const uint8_t address, const uint8_t values[], const uint8_t n) { obj->ncs = 0; obj->spi.write(MCP_WRITE); obj->spi.write(address); for (uint32_t i=0; i<n; i++) { obj->spi.write(values[i]); } obj->ncs = 1; } /** write to the specified MCP2515 transmit buffer from an array (needs one fewer SPI transfer than mcpWriteMultiple) */ void mcpWriteBuffer(mcp_can_t *obj, const uint8_t command, uint8_t values[], const uint8_t n) { obj->ncs = 0; obj->spi.write(command); for (uint32_t i=0; i<n; i++) { obj->spi.write(values[i]); } obj->ncs = 1; } /** initiate transmission of the specified MCP2515 transmit buffer */ void mcpBufferRTS(mcp_can_t *obj, const uint8_t command) { obj->ncs = 0; obj->spi.write(command); obj->ncs = 1; } /** read mcp2515's status register */ uint8_t mcpStatus(mcp_can_t *obj) { uint8_t status; obj->ncs = 0; obj->spi.write(MCP_READ_STATUS); status = obj->spi.write(0x00); obj->ncs = 1; return status; } /** read mcp2515's receive status register */ uint8_t mcpReceiveStatus(mcp_can_t *obj) { uint8_t status; obj->ncs = 0; obj->spi.write(MCP_RX_STATUS); status = obj->spi.write(0x00); obj->ncs = 1; return status; } /** modify bits of a register specified by a mask */ void mcpBitModify(mcp_can_t *obj, const uint8_t address, const uint8_t mask, const uint8_t data) { obj->ncs = 0; obj->spi.write(MCP_BITMOD); obj->spi.write(address); obj->spi.write(mask); obj->spi.write(data); obj->ncs = 1; }