Holt Hi-3110 User manual

AN-175 Rev. B Holt Integrated Circuits

ADK-175 User’s Guide –

HI-3110 Evaluation Board

April 2020

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AN-175

2 Holt Integrated Circuits

REVISION HISTORY

Revision

Date

Description of Change

AN-175 Rev. New

08-30-11

Initial Release

Rev. A

01-15-13

USB to Serial, External SPI Interface and Two node

demonstration.

Rev. B

04-20-2020

Improve board schematic diagram resolution.

Update Freescale Development Tools information.

Update document to new format.

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3 Holt Integrated Circuits

Introduction

The Holt HI-3110 ARINC 825 CAN BUS Controller Evaluation Board can be used to evaluate some of the

features of the HI-3110 CAN Controller IC with integrated transceiver. A Freescale MC9S12XDT512

microcontroller with 512K flash and 20K RAM communicates with the HI-3110 through the SPI interface.

The board includes switches and LEDs to help navigate the operating modes and confirm data and status

information. A Serial UART port is provided to allow debug and data messages to be sent to a PC using

any terminal program such as Hyper-terminal.

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4 Holt Integrated Circuits

KIT CONTENTS

This Users Guide.

HI-3110 Evaluation Board

HI-3110 Data Sheet

RS-232 Serial Cable

USB to Serial Adapter

Codewarrior™ Demo Software Project

Demonstration Features

Transmit Modes for Standard and Extended Frames

Receive Modes, polled and interrupt driven

CAN bus communication using two nodes

Monitor Mode

LoopBack Mode

Sleep Mode with wake-up from Button press or CAN data

Selectable Bit Rates from 83.3KBPS - 1MBPS

Print out the CAN buffers (64) on the serial console

Print out the status registers on the serial console

Print out the Transmit History FIFOs on the serial console

Print out the Error Status registers on the serial console

Configuring the INT, STAT and GP1 and GP2 outputs

SPI clock frequency selectable from 625 KHz –20 MHz.

Test Mode for cycling GPIOs and LEDs as a board check

CAN Filters and Masks

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5 Holt Integrated Circuits

Demonstration Set-up

MC9S12XD

16 Bit MCU

HOLT

HI-3110 CAN

Controller

SPI (4)

GP1,GP2,STAT,INT

RS-232 Console

USB Debug Port

DB9

CAN Bus

Connector

LEDs (10)

User Push

Button

Switches (4)

Dip SWs

(4) Dip SWs (6)

Expansion

Headers

(2x14) x 2

RESET Button

CAN

Transceiver

The board requires a +5V (0.5A) power supply applied to TP1 and Gnd to TP6. There are two ways to

connect the CANL and CANH signals to the CAN Bus. The CANL and CANH Bus signals are available on

the two test points on the top right side of the board or from the DB9 connector.

Power On Reset

For normal operation ensure SW2 –4 (MRST) is in the open position otherwise the MCU will be held in

the reset state. The purpose of this MRST dip switch is to allow easy interfacing of an external MCU to

the HI-3110 such that the SPI signals from the Freescale MCU will be forced into high impedance so as

not to conflict with an external MCU. For normal operation keep this switch open and use the RESET

button to reset the MCU during testing.

For Modes 1-6 the MCU will initialize the HI-3110 and check the STATF status register for the default

0x82 value, if the status value does not match 0x82 the program will turn on the Red LED8 and halt.

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6 Holt Integrated Circuits

CAN BUS Bit Rate selection

The Bit Rate can be selected by configuring the 3 dip switches in SW1. The program fetches the switch

positions once after a power up.

Bit Rate Selection

BIT RATE

1 MBPS

500 KBPS

250 KBPS

125 KBPS

83.3 KBPS

Mode Selection

MODE 2

MODE 1

MODE 0

MODE

Board Test

Transmit Standard Frames

Receive in polling mode

Monitor

Loop Back

Transmit Extended Frames

Receive in interrupt mode

Serial Console Commands

SW2 OPT1 switch (Receiver data frame compare)

Receiver Modes:

If OPT1 is in the open position the receiver mode will check the data frame for an incrementing 32-bit

value. If the data doesn’t match the expected value from the previous transmission it will turn on the

Red LED8 and halt.

Transmitter Modes:

If OPT1 is in the open position a 400us delay will be inserted between each transmission.

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7 Holt Integrated Circuits

SW2 OPT2 switch

OPT2 is also used in the receiver mode. It enables the FILTON bit(bit4) in the CTRL1 register for CAN ID

filtering. See the Receive Mode description in the software description section for more details.

Buttons1 –Button4 (SW1-SW4)

Depending on the mode these buttons will perform specific tasks.

Serial Port Configuration

The serial port is optional and provides access to additional status and data information:

Software Revision

Current Mode

CAN Frame data

CAN History FIFO data

Status Registers data

Sleep Mode status

Serial Commands Menu

A simple menu of commands is provided for resetting the HI-3110, reading and displaying the HI-3110

status registers, and a demo how to pass input strings to the program. There are provisions for

additional user code to be implemented so custom commands can be developed and easily integrated.

UART Serial Port Setup: 115200 Baud, 8 bits, No Parity, No handshaking.

A USB to Serial adapter is provided in the kit which can be used with PC’s that don’t have a serial port.

At power on reset (POR) the revision of the program will be displayed on the LEDs for two seconds in

binary format where LED1 is the LSB. After two seconds they will be turned off then LED7 will flash every

second as the main MCU “live” operating indicator. A message will also be sent to the Serial Port . For

Receive mode it will be shown as:

Holt HI 3110 Demonstration Software Revision: xx

Receive Mode polled

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8 Holt Integrated Circuits

Board Jumpers

JP1 - CAN BUS connector shield

JP2 - CANH 60 ohm termination.

JP3 - VDD jumper to U3 VLOGIC. Removing JP3 can be used to measure ICC.

JP4 - SPLIT termination voltage filter.

JP5 - CANL 60 ohm termination.

JP7 - VDD jumper to U3 VDD. Removing JP7 can be used to measure ICC or to operate the

logic section of the HI-3110 at 3.3V while keeping 5V on the VDD pin for the integrated

CAN transceiver. See the HI-3110 Split Voltage Operation section below.

Using the HI-3110 with an external MCU or FPGA

To use the HI-3110 with an external MCU or FPGA close the RESET DIP switch 4 in SW2. This will hold the

Freescale MCU in the reset state and keep the SPI signals from the Freescale MCU in tri-state. This

allows the SPI signals to be driven by an external source without having to remove the Freescale MCU

on the board. The SPI signals to the HI-3110 are available on both J8 header rows or J5 and J6. Refer to

the schematic for the pin assignments. Connect MR, nCS, SO, SI, SCK and optionally STAT and INT to the

external MCU or FPGA. The HI-3110 supports either 5V or 3.3V logic levels depending if 5V or 3.3V is

applied to the Vlogic pin. 5V is needed on the VDD pin for the transceiver outputs to meet ISO-11898-5

voltage levels.

HI-3110 Board Dual Voltage Configuration

It is possible to run the digital logic of the HI-3110 on 3.3V while keeping 5V on the integrated CAN

transceiver on the VDD pin-11. The Freescale MC9S12XD family can operate at either 3.3V or 5V so this

microcontroller can be used to demonstrate this. To setup the evaluation board for dual voltage

operation follow the simple setup instructions below:

Setup instructions:

1) Remove JP7 and connect the right side of the JP7 jumper post to TP2 VDD2. Do not re-

install the jumper shunt.

2) Connect a 3.3V power supply to the board TP1 VDD.

3) Connect a 5V power supply to the board TP2 VDD2.

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9 Holt Integrated Circuits

Users Guide

Mode-0: Board Test

In this mode the MCU performs a walking pattern on the GPIO pins and cycles turning on all the LEDs.

See the boardtest.c module for details and other options available.

Mode-1: Transmit Mode Standard Frames

This transmits a standard CAN frame with an incrementing 32-bit value in the first 4 bytes of the data –

field, the last four bytes will be 00. After RESET press the Button-1 to start the transmissions. A portion

of the data field will be copied to the LED1-LED4’s. They can be seen counting in this mode.

Press Button-1 to stop transmitting and print out the status registers on the serial console.

Press Button-2 to pause the transmission. Press Button-2 again to transmit one frame again.

Press Button-3 to print out the Transmit History FIFO contents on the serial console.

Press Button-4 to resume transmissions.

OPT1 switch= open, Inserts a 400us delay before each transmission.

Mode-2 Receive Mode using Polling method

To use Receive mode with an external node transmitter, set the OPT1 switch to the closed position to

disable the Receiver data frame compare feature. This will allow any data frame to be accepted.

LED1-4 will reflect the lower nibble of byte3 of the data-field.

CAN Error Detection

While receiving frames if there are any errors detected in the HI-3110 registers, TEC, REC or ERR, they

will be automatically logged on the Serial Port.

For example if ERR has a 01 value it would be shown as: ERR: 01. The other two errors will be shown

similarly.

Button-1 –Stop receiving CAN messages and print the last 64 CAN frames and the status registers on the

serial console. Press Button-4 to resume receiving CAN messages. See a partial listing of this output

below which shows the last two frames.

CAN Frame 62: 00 77 60 47 20 00 00 08 00 00 22 28 04 05 06 07

Standard Filter:0 TTU:77 TTL:60 BaseID:239

[r0,r1,x,x][DLC]: 08 Data-Field: 00 00 22 28 04 05 06 07

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10 Holt Integrated Circuits

CAN Frame 63: 00 78 61 47 20 00 00 08 00 00 22 29 04 05 06 07

Standard Filter:0 TTU:78 TTL:61 BaseID:239

[r0,r1,x,x][DLC]: 08 Data-Field: 00 00 22 29 04 05 06 07

Button-2 –Stop receiving CAN messages and print the HI-3110 status registers. Press Button-4 to

resume CAN messages.

CTR0 = 00

CTR1 = 00

BTR0 = 40

BTR1 = A7

TEC = 00

REC = 00

MESSTAT=00

STATF = 00

ERR = D8

INTF = 00

INTE = 82

STATFE= 00

GPINE = 00

TIMERUB=98

TIMERLB=95

Button-3 –Put the HI-3110 into Sleep Mode. Press Button-4 or send CAN messages in Sleep mode to

terminate and re-enter Normal mode. A message on the serial console will indicate the Sleep Mode and

the source to the wake-up event.

Holt HI-3110 Demonstration Software Revision: 09

Receive Mode polled

Entering SLEEP Mode

Press Button-4 to wake-up.

Normal Mode Resumed from Sleep Mode

Entering SLEEP Mode

Press Button-4 to wake-up.

Normal Mode Resumed from Monitor Mode

REC: 01 ERR: 04

The last line shows a BUS error that was caused when the HI-3110 was in Sleep Mode and woke up due

to a CAN message coming in.

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11 Holt Integrated Circuits

CAN bus communication using two nodes

Two-node communications can be demonstrated using two HI-3110 evaluation boards. One board is

configured in Mode-1 as the transmitter and the second board is configured in Mode-2 as the Receiver.

Two-node demo setup:

1. Connect CANH (TP3) from board-1 to CANH of board-2 together using a clip lead. Connect CANL

(TP4) signals together on each board using a clip lead. Optionally, a 9-pin CAN cable can also be

used in place of the clip leads (not provided in the kit).

2. Ensure the bit rate DIP switches S1, S2 and S3 are set for the same bit rate on both boards.

3. Set board-1 to Mode-1 as the Transmitting node. Mode-1 transmits an incrementing data pattern

starting from count zero.

4. Set board-2 to Mode-2 as the Receiver node. Set OPT1 switch to the open position to enable the

Receiver to perform 32-bit data frame compares.

5. Power up both boards and optionally press the Reset button on both boards.

6. To start the data transmissions press S1 on board-1.

Board-1 begins to transmit data frames and the Receiver board-2 will receive the data frames. The

Receive board LEDs 1-4 will reflect the lower nibble of byte3 of the data-field.

When OPT1 switch is open, The Receiver program will compare the 32-bit counter value in the data-field

and turn on the RED LED8 and halt if it does not match the expected value. To exit from the halt

condition, press the RESET button. To repeat the test after a data mismatch, reset both boards and

repeat the test by pressing the S1 on board-1 again. The data-field compare function can be turned off

by closing the OPT1 switch. With the compare function turned off, the Receiver will continue to receive

data frames and update the LEDs 1-4 from the lower nibble of byte3 of the data-field.

Mode-3 Monitor Mode

Monitor mode is a simple version similar to Receive mode but just captures the CAN data without

providing an acknowledge bit on the Bus.

Press Button-1 to stop receiving CAN messages and print the last 64 CAN frames and the HI-3110 status

registers on the serial console.

Press Button-4 to resume reception of CAN Messages.

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12 Holt Integrated Circuits

Mode-4 LoopBack Mode

LoopBack mode combines a Transmitter and Receiver function similar to the normal Transmit and

Receive modes. The Transmitter will transmit the 32-bit incrementing counter in the data-field and the

receiver looks and compares against this data pattern and will turn on the RED LED the same way as in

normal Receive Mode. No actual data is transmitted to the Bus in LoopBack mode.

Button-2 - Stops transmitting CAN data and prints out the contents of the Transmit History FIFO as

shown below. Press Button-4 to continue.

History FIFO: 04 86 00

History FIFO: 04 87 00

History FIFO: 04 87 81

History FIFO: 04 88 03

History FIFO: 04 88 84

History FIFO: 04 89 06

History FIFO: 04 4D E2

Button-1 –Stop receiving CAN messages and prints the last 64 CAN frames and the HI-3110 status

registers on the serial console. Press Button-4 to resume receiving CAN Messages.

Mode-5 Transmit Extended Frames

This is the same as Transmit Mode-1 but with Extended Frame format.

Mode-6 Receiver Interrupt Mode

This is very similar to normal Receive mode-2 but without Sleep Mode. The main purpose is to

demonstrate how to use interrupts to received the CAN Bus data in the background.

Press Button-1 to stop receiving CAN messages and print the last 64 CAN frames and the HI-3110 status

registers on the serial console.

Press Button-4 to resume reception of CAN messages.

AN-175 
 
13 Holt Integrated Circuits 
Mode-7 Serial Commands Menu 
After a power on reset, a simple text menu will be displayed on the serial console: 
************** HOLT HI-3110 Serial Console Commands 
 
 Input String Demo 0 
 Reset 1 
 Status Register Read 2 
 Filter Incrementing 3 
 
 Enter Selection:2 
 
Enter “1” to generate a hardware reset to the HI-3110. 
 
Enter “2” for the status register read and display: 
 
CTR0 =80 
CTR1 =00 
BTR0 =00 
BTR1 =00 
TEC =00 
REC =00 
MESSTAT =00 
STATF =00 
ERR =00 
INTF =00 
INTE =82 
STATFE =00 
GPINE =00 
TIMERUB =0D 
TIMERLB =66 
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14 Holt Integrated Circuits 
Software Description 
 
The software project is built with Freescale’s Codewarrior version 5.9.0 using the free version which is 
limited to 32K code size. The current code size is approximately 10.5K. The main functions are in main.c 
and the lower level HI-3110 drivers are in the 3110Driver.c file. Some program flow charts are provided 
to help clarify some of the program. 
Project Files 
 
Source Files 
 
 main.c Main code 
3110Driver.C SPI low-level drivers for the HI-3110 
 Peripherals.c GPIO, PLL frequency setup and SPI configuration 
 BoardTest.c Board Test functions 
 Uart.c Low-level UART drivers 
 datapage.c Freescale IDE support file 
 
Include Files 
 
 Main.h 
 3110Driver.h HI-3110 header file 
 Peripherals.h Peripherals header file 
 BoardTest.H Board test header file 
 Uart.h Uart header file 
 Common.h Common defines for the project 
 Derivative.h Freescale IDE support file 
 Mc9s12xdt512.h Freescale IDE target part support file 
 
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15 Holt Integrated Circuits

Main Flow Chart

Initialize GPIOs

GPIO interrupts

Initilize Timer0 periodic interrupt 100us

Display program revision on LEDs

Turn off all LEDs

Display header message on the serial console

Generate a hardware reset to the HI-3110

Test Mode?

Main.c

Transmit

Mode?

Receive Mode?

Serial

Commands?

Read Option Switches

Read Mode switches

Monitor Mode?

Loopback

Mode?

Receive

Interrupt

Mode?

Transmit Ext

Mode?

Test Mode

Transmit Mode

Receive Mode

Monitor Mode

Loopback Mode

Transmit Extended

Frame Mode

Receive Interrupt Mode

Serial Commands

Yes

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16 Holt Integrated Circuits

Interrupt Flow Charts

Timer_ISR

Reload for next interrupt

Decrement g_count100us tick

1 second

handler?

return

Flash LED7

Yes

PortP_ISR

PP2 GP2 Pin?

return

Yes

PP3 GP1 Pin?

For Modes 1, 5

and 6

Fetch RX FIFO Data

Set Ready Flag

Clear Interrupt

Set G_TCPLTIE Flg

Clear Interrupt

Yes

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17 Holt Integrated Circuits

Receiver Mode 1 Flow Chart

Receive Mode 2

Flash LED2

Initialize the UART

Print out mode on serial console

Initialize 3110? Turn on LED8

Halt

Initialize the GPINE pins

Initialize the STAT pin for RXFMTY

Clear the 64 frame buffer

SW1 button

pushed?

SW2 button

pushed?

SW3 button

pushed?

Get Error Status’

Get Status Flag

RXFMTY?

Stop and display 64

CAN frames

Stop and display

Status Registers

Stop and enter

Sleep Mode

fail

pass

Fetch Frame Data and load into

RXBuffer

Load LEDs1-4 with byte-3 of data-

field

OPT1 switch

open?

Increment 32-bit counter

Increment message count

Message count

= 64?

32-bit counter

compare?

Turn on RED

LED8 and Halt

Yes

SW4 button

pushed to

resume?

Yes

Reset Message

count to 0

Yes

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18 Holt Integrated Circuits

Transmitter Modes 1 and 5 Flow Chart

Transmitter Mode 1

Flash LED1

Initialize the UART

Print out mode on serial console

Initialize

3110? Turn on LED8

Halt

Initialize the GPINE pins for

GP1=TXCPLT, GP2=RXFIFO

Clear TXBuffer

Print “Press Button-1 to start”

SW1 button

pushed?

SW2 button

pushed?

SW3 button

pushed?

Print Status

Regs

fail

pass

Yes

Wait for

Button-1

Pause

Print History

FIFO

Load 8 Std or Ext

Frames into FIFO

FIFO Empty?

OPT1 SW

open? Wait 100us

Wait for

TXCPLT

Yes

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19 Holt Integrated Circuits 
MCU Clock and SPI Frequency 
 
The Freescale MC9S12XDT512 (MCU) uses a 4MHz crystal for operation and the built-in PLL is used to 
multiply this by 20 to achieve an 80MHz system clock. This system clock is divided by two for a 40MHz 
Bus Clock which is used internally for the MCU peripherals. 
The PLL is programmed to multiply by 20 by this line: 
 
SYNR = 9; // 80Mhz PLL system clock 
 
The SPI frequency is set by this line of code: 
 
 SPI0BR = SPI_5MHZ; // SPI CLK = 5MHz (see 
 // “peripherals.c”  for other rates) 
 
Timer Interrupt and timings 
 
A 100us Timer0 interrupt supports basic timings. A number of predefined constants are provided to 
allow some common delays passed into the Delay100us() function: 
 
#define K_1MS 10 
 #define K_10MS 100 
 #define K_100MS 1000 
 #define K_1SEC 10000 
 
Usage: Delay100us(K_1SEC); // delay for one second 
A one second interrupt handler in the TIMER_ISR is provided. Any code placed here will automatically 
get executed every second. 
if (!count100us) 
 { // 1 second scheduler 
count100us = K_1SEC; 
if(ON==g_ledFlashBool) // Flash the 
 LED8 ^= TOGGLE; // Alive 1 second blink 
 } 
 
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AN-175 
 
20 Holt Integrated Circuits 
HI-3110 Interrupts 
 
The HI-3110 can be configured to output status on the INT, STAT, GP1 and GP2 pins which connect to 
the MCU PP0 –PP3 inputs. Interrupt handlers are provided for the GP1 and GP1 for servicing TXCPLT 
and RXFIFO respectively on the PP3 and PP2 pins which are enabled by calling PortP_Int(). 
 Interrupt 56 void PORTP_ISR(void) 
The PP2 interrupt handler is provided to interrupt when the 3110 receives a CAN Bus frame of data. This 
interrupt handler is utilized only in Receive Mode Interrupt Mode-6. Once an interrupt occurs the 
interrupt handler fetches the frame of data and stores the data into a global buffer (g_RXBuffer) and 
then sets a flag “g_RecRdy=TRUE”. The main receiver function looks for this flag and fetches the new 
CAN data when this flag is set. 
There are two other possible sources for hardware interrupts using the XIRQ and IRQ inputs reserved for 
possible future use. 
 
3110Driver.c Drivers 
 
All the HI-3110 SPI drivers are contained in this module for reading and writing to the control registers, 
status registers, filters/masks and FIFO’s . 
There are several functions to read in a single byte from the 3110 SPI port, write a command to the 3110 
SPI port and a few others which read or write a command plus a multiple number of bytes. For example 
the function below is the basic function to write out a command plus one byte of data to the 3110 SPI 
port. 
 
// Write SPI Command with a Value to HI-3110 
void W_CommandValue (uint8 cmd, uint8 value){ 
 uint8 dummy; 
 
 SPI0CR1 = SPI0CR1 & ~SPI0CR1_SSOE_MASK; // disable auto /SS output, reset /SS Output 
 SPI0CR2 = SPI0CR2 & ~SPI0CR2_MODFEN_MASK; // disable auto /SS output, reset SPI0 Mode 
 SPI0_nSS = 0; // assert the SPI0 /SS strobe 
 dummy = SPI0SR; // clear SPI status register 
 SPI0DR = cmd; // SPI command 
 while (!SPI0SR_SPIF); 
 dummy = SPI0DR; // read Rx data in Data Reg to reset SPIF 
 dummy = SPI0SR; // clear SPI status register 
 SPI0DR = value; // Reset values 
 while (!SPI0SR_SPIF); 
 dummy = SPI0DR; // read Rx data in Data Reg to reset SPIF 
 
 SPI0_nSS = 1; // negate the SPI0 /SS strobe 
 SPI0CR1 = SPI0CR1 | SPI0CR1_SSOE_MASK; // enable auto /SS output, set /SS Output 
 SPI0CR2 = SPI0CR2 | SPI0CR2_MODFEN_MASK; // enable auto /SS output, set SPI0 Mode Fault 
} 
 
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