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Programming and GPIO

MS_uC / dnd / V07

Programming MicrocontrollerIDE usage, debugger

GPIO – General Purpose Input/OutputWeek 2 - autumn term 2007

32K Byte 32K Byte Burst FlashBurst Flash

64K or 96K 64K or 96K Byte SRAM Byte SRAM

256K or 512K 256K or 512K Byte Burst Byte Burst

FlashFlash

OTP OTP MemMem

UARTUARTI2CI2CSPISPITIMTIMRTCRTC

EXT. EXT. Bus Bus

GPIOGPIO

USB USB 2.0FS 2.0FS

CAN CAN 2.0B 2.0B

Enet Enet MAC MAC

PFPFQ Q

BC BC

DMADMA

INTINTR R

CntlCntl

ARM96ARM966E 6E CORE CORE

w/DSPw/DSP96 MHz 96 MHz

CLK CLK CntlCntl

ADCADC

LVD LVD BODBOD

PLLPLL JTAJTAGG

ETMETM99

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Programming and GPIO

MS_uC / dnd / V07

Please copy examples to a directory of your choice

Blinky

MyFolder

programme\keil\arm\boards\keil\mcbstr9\

copy

uVision: [Project -> Open Project ...]

Select a .uv2 file which is a project file

Check processor type:

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Programming and GPIO

MS_uC / dnd / V07

compiling Blinky.c...compiling LCD.c...compiling UserFont.c...linking...Program Size: Code=2264 RO-data=96 RW-data=4 ZI-data=1292 ".\Flash\Blinky.axf" - 0 Error(s), 0 Warning(s).

[Project -> Rebuild all target files]

No errors, no warnings is what

we like to see

Generated files are found in the Flash folder of the project directory:

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Programming and GPIO

MS_uC / dnd / V07

Debug commands

Debugging the application:

Breakpoint:

Execution stopped. Line 055 will be executed next

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Programming and GPIO

MS_uC / dnd / V07

Processor insight

Only accessible if target is not running

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Programming and GPIO

MS_uC / dnd / V07

System and Clock settings

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Programming and GPIO

MS_uC / dnd / V07

Peripheral Bridge 1 configuration"slow" peripherals

PCG1: Peripheral Clocking Gate Register 1: 0PRR1: Peripheral Reset Register 1: 0

GPIO7 enabled (LED)After Reset: ports disabled

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Programming and GPIO

MS_uC / dnd / V07

Definition

A GPIO is a digital binary signal Its switching level depends on the technology used A GPIO normally is programmable as unconnected,

input, output A GPIO might have built-in elements like pull-up,

pull-down or ESD devices A GP Output signal is able to sink (or source) a

defined amount of current A GP Input has a defined Impedance which might

be taken into account if a passive sensor is linked to it

A GP Input has a defined hysteresis to avoid "flippering" of the signal "Schmitt Trigger input"

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Programming and GPIO

MS_uC / dnd / V07

GPIO debug support in IDE peripherals

[Peripherals-I/O Ports]

P3 as inputP3.6 activeSCU_GPIOIN3: all bits connected to input

GPIO_DIR7: all bits as outputSCU_GPIOOUT7: all bits output Altern1SCU_GPIOIN7: no copy to input pinsSCU_GPIOTYPE7: push-pull output

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Programming and GPIO

MS_uC / dnd / V07

General Purpose I/O

Variable Pin attribution:

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Programming and GPIO

MS_uC / dnd / V07

Pin assignment for peripherals

Peripheral

# No of Unit

Port Assignment

IO Mode Peripheral

# No of Unit

Port Assignment

IO Mode

ADC 8 chann-els

P4 Always Connected

Motor Control

1 P6 Alt Out

CAN 1 P1, P3, P5 Alt In Alt out

SSP 2 P2, P5 Alt In Alt Out

ETM 1 P0,P2,P4,P5,P6, P7

Alt In Alt Out

Timers 4 P0, P4, P6, P7

Alt In Alt Out

Ethernet MAC

1 P0, P1, P5 Always Connected

UART 3 P1, P2, P3, P5, P6, P7

Alt In Alt Out

EMI Mux P8, P9, P7 P7 – Alt Out

USB 1 D+/D- Ext clk – P3

Dedicated pins

Non-mux

P8, P9, P7 P7 – Alt Out

External Interrupt

30 P3, P5, P6, P7

Always Connected

Chip Select

4 P0, P5, P7 Alt Out External DMA Req

2 P3 Always Connected

I2C 2 P0, P1, P2 Alt In Alt Out

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Programming and GPIO

MS_uC / dnd / V07

GPIO Configuration Registers

SCU_GPIOOUT – select alternative output for a peripheral

SCU_GPIOIN- specify input to a peripheral

SCU_GPIOTYPE- Open Collector or Push-pull GPIO_DIR – specify direction for standard I/O

pin GPIO_Data – Data register for standard I/O pin

SCU_GPIOTYPERegister

SCU_GPIOOUTRegister

GPIO_DIRRegister

GPIO_DataRegister

ALT 1 Output

Peripherals

ALT 2 Output

ALT 3 Output

APB Bus

SCU_GPIOINRegister

OUT

IN

Always Connected (to ADC, Interrupt etc)

GPIO PIN

®

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Programming and GPIO

MS_uC / dnd / V07

GPIO signal flow

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Programming and GPIO

MS_uC / dnd / V07

GPIO registers

SCU_GPIOOUTn

SCU_GPIOINn

SCU_GPIOTYPEmPush-pullOpen collector

n : [9:2] Port number and alternate function

GPIO_DATA

GPIO_DIR

00h..3FCh [7..0]

GPIO_SEL

400h

420h

APB0_Base +

Ex: GPIO7 direction register non-buffered: 0x5800 D400

SCU_PCGR1_Val

SCU_PRR1_Val

In File STR91x.s:

Peripheral Clock Gating Register

Peripheral Reset Register

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Programming and GPIO

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ARM Peripheral Bus 0 access (APB0)

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Programming and GPIO

MS_uC / dnd / V07

GPIO Access through Memory

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Programming and GPIO

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Library source

Library examples

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Programming and GPIO

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Add library files with new path if necessary:

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Programming and GPIO

MS_uC / dnd / V07

Debugging system variables: SCU : System Control Unit

1.) Add a static pointer variable to SCU:

int main(){

static SCU_TypeDef *sb = SCU;…..

2.) In Debug mode, add this variable to the watch window ( put cursor onto "sb", then right click)

3.) The structured variable is now visible at address 0x5C00 2000

Changes in variables will be highlighted when stepping trough the program

There is no live debug symbol or memory updates when the processor is running

0x5C002060 will show GPIO_OUT7