Entity: i2cslv
- File: i2cslv.vhd
Diagram
Description
This file is a part of the GRLIB VHDL IP LIBRARY Copyright (C) 2003 - 2008, Gaisler Research Copyright (C) 2008 - 2012, Aeroflex Gaisler
This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
Entity: i2cslv File: i2cslv.vhd Author: Jan Andersson - Gaisler Research jan@gaisler.com
Description: Simple I2C-slave with AMBA APB interface
Documentation of generics:
[hardaddr] If this generic is set to 1 the core uses i2caddr as the hard coded address. If hardaddr is set to 0 the core's address can be changed via the SLVADDR register.
[tenbit] Support for ten bit addresses.
[i2caddr] The slave's (initial) i2c address.
[oepol] Output enable polarity
[filter] Length of filters used on SCL and SDA
The slave has four different modes operation. The mode is defined by the value of the bits RMODE and TMODE. RMODE TMODE I2CSLAVE Mode 0 0 0 0 1 1 1 0 2 1 1 3
RMODE 0: The slave accepts one byte and NAKs all other transfers until software has acknowledged the received byte. RMODE 1: The slave accepts one byte and keeps SCL low until software has acknowledged the received byte TMODE 0: The slave transmits the same byte to all if the master requests more than one byte in the transfer. The slave then NAKs all read requests unless the Transmit Always Valid (TAV) bit in the control register is set. TMODE 1: The slave transmits one byte and then keeps SCL low until software has acknowledged that the byte has been transmitted.
Generics
| Generic name | Type | Value | Description |
|---|---|---|---|
| pindex | integer | 0 | slave bus index |
| paddr | integer | 0 | |
| pmask | integer | 16#fff# | |
| pirq | integer | 0 | interrupt index |
| hardaddr | integer range 0 to 1 | 0 | See description above |
| tenbit | integer range 0 to 1 | 0 | |
| i2caddr | integer range 0 to 1023 | 0 | |
| oepol | integer range 0 to 1 | 0 | |
| filter | integer range 2 to 512 | 2 |
Ports
| Port name | Direction | Type | Description |
|---|---|---|---|
| rstn | in | std_ulogic | |
| clk | in | std_ulogic | |
| apbi | in | apb_slv_in_type | APB signals |
| apbo | out | apb_slv_out_type | |
| i2ci | in | i2c_in_type | I2C signals |
| i2co | out | i2c_out_type |
Signals
| Name | Type | Description |
|---|---|---|
| r | i2cslv_reg_type | --------------------------------------------------------------------------- Signals --------------------------------------------------------------------------- Register interface |
| rin | i2cslv_reg_type | --------------------------------------------------------------------------- Signals --------------------------------------------------------------------------- Register interface |
Constants
| Name | Type | Value | Description |
|---|---|---|---|
| I2CSLV_REV | integer | 0 | |
| PCONFIG | apb_config_type | ( 0 => ahb_device_reg(VENDOR_GAISLER, GAISLER_I2CSLV, 0, I2CSLV_REV, pirq), 1 => apb_iobar(paddr, pmask)) |
AMBA PnP |
| SLV_ADDR | std_logic_vector(7 downto 2) | "000000" | Register addresses |
| CTRL_ADDR | std_logic_vector(7 downto 2) | "000001" | |
| STS_ADDR | std_logic_vector(7 downto 2) | "000010" | |
| MSK_ADDR | std_logic_vector(7 downto 2) | "000011" | |
| RD_ADDR | std_logic_vector(7 downto 2) | "000100" | |
| TD_ADDR | std_logic_vector(7 downto 2) | "000101" | |
| TENBIT_SUPPORT | integer | tenbit | Core configuration |
| I2CADDRLEN | integer | 7 + tenbit*3 | |
| HARDCADDR | integer | hardaddr | |
| I2CSLVADDR | std_logic_vector((I2CADDRLEN-1) downto 0) | conv_std_logic_vector(i2caddr, I2CADDRLEN) |
|
| I2C_READ | std_ulogic | '1' | R/Wn bit |
| I2C_WRITE | std_ulogic | '0' | |
| OEPOL_LEVEL | std_ulogic | conv_std_logic(oepol = 1) | |
| I2C_LOW | std_ulogic | OEPOL_LEVEL | OE |
| I2C_HIZ | std_ulogic | not OEPOL_LEVEL | |
| I2C_ACK | std_ulogic | '0' | |
| TENBIT_ADDR_START | std_logic_vector(4 downto 0) | "11110" |
Types
| Name | Type | Description |
|---|---|---|
| ctrl_reg_type | --------------------------------------------------------------------------- Types --------------------------------------------------------------------------- | |
| sts_reg_type | ||
| slvaddr_reg_type | ||
| i2cslv_reg_bank | ||
| i2c_in_array | ||
| slv_state_type | (idle, checkaddr, check10bitaddr, sclhold, movebyte, handshake) |
|
| i2cslv_reg_type |
Functions
- compaddr1stb ( ibyte : std_logic_vector(7 downto 0);
-- I2C byte sr : slvaddr_reg_type) return boolean
Description
Subprograms
purpose: Compares the first byte of a received address with the slave's
address. The tba input determines if the slave is using a ten bit address.
- compaddr2ndb ( ibyte : std_logic_vector(7 downto 0);
-- I2C byte slvaddr : std_logic_vector((I2CADDRLEN-1) downto 0)) return boolean
Description
purpose: Compares the 2nd byte of a ten bit address with the slave address
Processes
- comb: ( r, rstn, apbi, i2ci )
- reg: ( clk )
Instantiations
- bootmsg: report_version
Description
Boot message
pragma translate_off