AN4274
Application note
The serial communication driver between
the ST7580 and the STM32Fx
By Vincenzo Mormina
Introduction
This document describes the serial communication driver between the ST7580 and the
STM32Fx.
This driver is designed from ST7580 power line modem devices.
This firmware is available by software license agreement only:
• http://www.st.com/software_license_agreement_liberty_v2
• http://www.st.com/software_license_agreement_image_v2
Please, ask your local ST office for further information.
April 2013
DocID024358 Rev 1
1/13
www.st.com
Contents
AN4274
Contents
1
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2
Firmware architecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3
Board support package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
4
Serial communication layer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
5
Reference documents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Appendix A Example of serial communication driver code . . . . . . . . . . . . . . . . 10
Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
2/13
DocID024358 Rev 1
AN4274
1
Overview
Overview
The ST7580 serial communication driver provides services and functions to manage the
serial communication (UART, USART) from the ST7580 power line networking SoC and the
STM32Fx microcontroller.
The STM32Fx hardware resources required to connect the STM32Fx to ST7580 PLM are:
•
Serial peripheral (Uart/Usart)
•
3 GPIO
•
Timer
The ST7580 serial communication driver provides the function to configure these
peripherals.
The ST7580 serial communication driver is based on the STM32Fx standard library to
manage the peripherals used.
For further details about the serial peripherals and the accepted configuration parameters,
please see the ST7580 and the STM32Fx documentation.
DocID024358 Rev 1
3/13
Firmware architecture
2
AN4274
Firmware architecture
Figure 1 shows the firmware architecture:
Figure 1. Firmware architecture
Application
STM32
Serial comm driver
BSP
STM32 std driver
ST7580
Physical
AM16729v1
•
Physical:
–
•
STM32Fx standard driver:
–
•
it provides a serial communication function to manage the communication from the
ST7580 to STM32Fx and vice versa.
Application layer:
–
4/13
the BSP layer defines and configures the communication peripherals used to
connect the ST7580 and the STM32Fx.
Serial communication driver:
–
•
it provides the STM32Fx standard peripheral driver.
BSP (board support package):
–
•
the physical layer of the ST7580 provides a basic MAC service through a serial
communication interface.
the application layer can be customized by the user; in this section the user must
design the application.
DocID024358 Rev 1
AN4274
Firmware architecture
The following Figure 2 and Figure 3 show the component files.
Figure 2. Serial communication driver files
STM32
ST7580_serial20.h
ST7580_serial20.c
Serial comm driver
AM16730v1
The serial communication firmware module contains the files ST7580_Serial20.c/h.They
provide FSM (finite state machine) and the functions to manage the serial data flow from
and to the ST7580 devices.
Figure 3. BSP files
STM32
ST7580_STM32_ bsp.h
ST7580_STM32_bsp.c
BSP
AM16731v1
The BSP firmware module contains all the definitions and the configurations of the hardware
resources used by the system to perform and manage the connection and serial
communication from the ST7580 to the STM32Fx and vice versa.
DocID024358 Rev 1
5/13
Board support package
3
AN4274
Board support package
This layer defines the STM32Fx peripherals used to perform the serial communication. In
this file the following peripherals and linked functions have to be defined:
6/13
•
Uart/Usart: serial connection.
•
GPIO: used by Uart/Usart, to reset the ST7580 and MCO pin if used.
•
Timer: used by serial synchronization and timeout.
•
MCO: external clock, if used.
DocID024358 Rev 1
AN4274
4
Serial communication layer
Serial communication layer
The serial communication module defines all the functions to manage the serial data flow.
The core of the serial communication driver is a "ModemComFSM" function. This is a finite
state machine and must be called in an infinite loop, as follows:
while(1)
{
state = ModemComFSM( &SerCom, DL_Act);
switch (state)
{...}
}
This function has the following input parameters:
•
SerCom, input/output parameter. It is a pointer to "SER_CMD_FRAME_T" struct:
typedef struct{
u8 id;//host interface command code
u8 Rxpar_len;//reception buffer length
u8 Txpar_len; //transmission buffer length
u8 Rxparam[255];//reception buffer
u8 Txparam[255];//transmission buffer
} SER_CMD_FRAME_T;
•
DL_Act, this parameter notifies that the data is ready to be sent; the user sets "1" to
send the data.
Table 1 defines the return values of the finite state machine:
Table 1. FSM return values
Name
Value
FSM state
M_FRAME_ACKED
04h
1
Frame sent to PLM and ACK arrived.
M_FRAME_NOT_ACKED
05h
1
Frame sent to PLM and NACK arrived
(error state).
M_WAIT_ACK
06h
1
FSM waits for either ACK or NACK
after sending data.
M_FRAME_RECEIVED
07h
2
FSM received the data from a PLM,
and the data is ready to be read.
M_IDLE
08h
2
The FSM is ready to receive the data
from STM32Fx to be sent to PLM.
M_FRAME_VALID
09h
2
The data received by STM32Fx is valid.
M_FRAME_NOT_VALID
0Ah
2
The data received by STM32Fx is not
valid (error state).
M_FRAME_DELIVERED
0Bh
3
The FSM delivered the data to PLM.
M_WAIT_STATUS
0Ch
3
The FSM waits for the status of the
message from PLM.
M_FRAME_CONFIRMED
0Dh
4
The data sent to PLM is confirmed.
DocID024358 Rev 1
Description
7/13
Serial communication layer
AN4274
Table 1. FSM return values (continued)
Name
Value
FSM state
Description
M_FRAME_NOT_CONFIRMED
0Eh
4
The data sent to PLM is not confirmed
(error state).
M_WAIT_CONFIRM
0Fh
4
The FSM waits for the confirmed
command from PLM.
M_TO_ELAPSED
10h
1-3-4
Timeout elapsed (error state).
The application layer can send frames to PLM only when the FSM return state is "M_IDLE.
If the data sent to FSM is valid, the FSM return state is "M_FRAME_RECEIVED".
8/13
DocID024358 Rev 1
AN4274
5
Reference documents
Reference documents
•
ST7580 datasheet
•
UM0932 user manual
•
AN4068 application note
•
STM32Fx datasheet
DocID024358 Rev 1
9/13
Example of serial communication driver code
Appendix A
AN4274
Example of serial communication driver code
The following code shows how to manage the serial communication driver.
The "BSP_Init" is a configuration function, the parameter "COM_BAUD_RATE" is the serial
speed (please see the ST7580 datasheet for further details about the accepted speed
values).
The FSM must be inserted in an infinite loop, and the return state must be managed.
The state "M_FRAME_RECEIVED" notifies that a new data has arrived, the state "M_IDLE"
means that the FSM is free and the data can be sent.
/* init BSP */
BSP_Init(COM_BAUD_RATE);
/* Output HSE clock on MCO pin */
EnableMCO();
/*start Modem*/
MODEM_START;
while(1)
{
u8 state;
state = ModemComFSM( &SerCom, DL_Act);
switch (state)
{
case M_FRAME_RECEIVED:// Frame Receive Management
{
/* reception management, example */
Id_Command = SerCom.id;
memcpy(&RX_Buff, &SerCom.Rxparam, SerCom.Rxpar_len);
RX_Buffer_Len = SerCom.Rxpar_len;
}
break;
case M_IDLE:// Frame Transmit Management
{
/* Transmission management, example */
if(TX_State == APP_TRUE){
SerCom.id = 0x50;//DL_Data Req ID
SerCom.Txparam[0] = 0x04;//Modem Transmission Parameters
SerCom.Txparam[1] = 0x01;//Data 1
SerCom.Txparam[2] = 0x03;//Data 2
SerCom.Txpar_len = 3;
DL_Act = ACT_TX;
TX_State = APP_FALSE;
}
}
break;
case M_FRAME_CONFIRMED:
10/13
DocID024358 Rev 1
AN4274
Example of serial communication driver code
{
}
break;
case M_FRAME_NOT_CONFIRMED:
{
/* put here the Frames not Confirmed Management CODE */
DL_Act = NO_ACT;
}
break;
case M_TO_ELAPSED:
break;
case M_FRAME_VALID:
break;
default:
{
state = M_IDLE;
}
break;
}
}
DocID024358 Rev 1
11/13
Revision history
AN4274
Revision history
Table 2. Document revision history
12/13
Date
Revision
23-Apr-2013
1
Changes
Initial release.
DocID024358 Rev 1
AN4274
Please Read Carefully:
Information in this document is provided solely in connection with ST products. STMicroelectronics NV and its subsidiaries (“ST”) reserve the
right to make changes, corrections, modifications or improvements, to this document, and the products and services described herein at any
time, without notice.
All ST products are sold pursuant to ST’s terms and conditions of sale.
Purchasers are solely responsible for the choice, selection and use of the ST products and services described herein, and ST assumes no
liability whatsoever relating to the choice, selection or use of the ST products and services described herein.
No license, express or implied, by estoppel or otherwise, to any intellectual property rights is granted under this document. If any part of this
document refers to any third party products or services it shall not be deemed a license grant by ST for the use of such third party products
or services, or any intellectual property contained therein or considered as a warranty covering the use in any manner whatsoever of such
third party products or services or any intellectual property contained therein.
UNLESS OTHERWISE SET FORTH IN ST’S TERMS AND CONDITIONS OF SALE ST DISCLAIMS ANY EXPRESS OR IMPLIED
WARRANTY WITH RESPECT TO THE USE AND/OR SALE OF ST PRODUCTS INCLUDING WITHOUT LIMITATION IMPLIED
WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE (AND THEIR EQUIVALENTS UNDER THE LAWS
OF ANY JURISDICTION), OR INFRINGEMENT OF ANY PATENT, COPYRIGHT OR OTHER INTELLECTUAL PROPERTY RIGHT.
ST PRODUCTS ARE NOT AUTHORIZED FOR USE IN WEAPONS. NOR ARE ST PRODUCTS DESIGNED OR AUTHORIZED FOR USE
IN: (A) SAFETY CRITICAL APPLICATIONS SUCH AS LIFE SUPPORTING, ACTIVE IMPLANTED DEVICES OR SYSTEMS WITH
PRODUCT FUNCTIONAL SAFETY REQUIREMENTS; (B) AERONAUTIC APPLICATIONS; (C) AUTOMOTIVE APPLICATIONS OR
ENVIRONMENTS, AND/OR (D) AEROSPACE APPLICATIONS OR ENVIRONMENTS. WHERE ST PRODUCTS ARE NOT DESIGNED
FOR SUCH USE, THE PURCHASER SHALL USE PRODUCTS AT PURCHASER’S SOLE RISK, EVEN IF ST HAS BEEN INFORMED IN
WRITING OF SUCH USAGE, UNLESS A PRODUCT IS EXPRESSLY DESIGNATED BY ST AS BEING INTENDED FOR “AUTOMOTIVE,
AUTOMOTIVE SAFETY OR MEDICAL” INDUSTRY DOMAINS ACCORDING TO ST PRODUCT DESIGN SPECIFICATIONS.
PRODUCTS FORMALLY ESCC, QML OR JAN QUALIFIED ARE DEEMED SUITABLE FOR USE IN AEROSPACE BY THE
CORRESPONDING GOVERNMENTAL AGENCY.
Resale of ST products with provisions different from the statements and/or technical features set forth in this document shall immediately void
any warranty granted by ST for the ST product or service described herein and shall not create or extend in any manner whatsoever, any
liability of ST.
ST and the ST logo are trademarks or registered trademarks of ST in various countries.
Information in this document supersedes and replaces all information previously supplied.
The ST logo is a registered trademark of STMicroelectronics. All other names are the property of their respective owners.
© 2013 STMicroelectronics - All rights reserved
STMicroelectronics group of companies
Australia - Belgium - Brazil - Canada - China - Czech Republic - Finland - France - Germany - Hong Kong - India - Israel - Italy - Japan Malaysia - Malta - Morocco - Philippines - Singapore - Spain - Sweden - Switzerland - United Kingdom - United States of America
www.st.com
DocID024358 Rev 1
13/13