ST AN1528 Application note

AN1528

APPLICATION NOTE

ST92F120/F124/150/F250 TESTFLASH

INTRODUCTION

The testflash is a ST reserved flash area that contains device information, flash parameters and the boot code. This boot code contains the protocol for In-System Programming and the routines for E3TM initialization and management. The testflash is programmed by ST at the factory before shipping and cannot be erased or programmed in user mode.

The purpose of this document is to give an sufficiently accurate description of the testflash content to allow the user to access to the different parameters and routines included in the testflash.

After an overview of the testflash content, the document describes the different routines that can be called at any time by the user code. The last part of this document provides guidelines on the way to handle an E3TM failure.

1 GLOSSARY AND ACRONYMS

The terms, abbreviations and acronyms used in this document are listed below and described in alphabetical order.

–CONFxR: CONFiguration x Register

–NVAPR: Non Volatile Access Protection Register

–NVCSSx: NV Complementary Sector Status x

–NVESPx: NV Emulation Status Pointer x

–NVPWDx: Non Volatile PassWorD x

–NVWPR: Non Volatile Write Protection Register

–REDxR: REDundancy x Register

–VCSSx: Volatile Complementary Sector Status x

–VESPx: Volatile Emulation Status Pointer x

Rev. 3.0

AN1528/0105

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Table of Contents

INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1 GLOSSARY AND ACRONYMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 2 OVERVIEW . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 2.1 VECTOR TABLE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

2.1.1 Device identifier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 2.1.2 Testflash code revision . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

2.2 USER OTP AREA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 2.3 PROTECTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 3 ROUTINES DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 3.1 POWER-ON ROUTINE (230020H) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 3.2 NON MASKABLE INTERRUPT ROUTINE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 3.3 CODE UPDATE ROUTINE: IN-SYSTEM PROGRAMMING . . . . . . . . . . . . . . . . 8

3.4 E3TM INITIALIZATION ROUTINE (230026H) . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

3.5 E3TM SWAP ERROR ROUTINES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

3.5.1 Find Wrong Pages (230029h) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 3.5.2 Find Wrong Bytes (23002Ch) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 3.5.3 Complete Aborted Swap (23002Fh) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

3.6 E3TM RESET TO DELIVERY STATUS (230032H) . . . . . . . . . . . . . . . . . . . . . . 14 3.7 USER ROUTINE FOR EXTERNAL WATCHDOG REFRESH . . . . . . . . . . . . . . 15

4 E3TM FAILURE RECOVERY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 4.1 ERASE OR WRITE ERROR: FATAL ERROR . . . . . . . . . . . . . . . . . . . . . . . . . . 17 4.2 SWAP ERROR: NON FATAL ERROR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

4.2.1 Generate a reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 4.2.2 Call the “complete aborted swap phase” routine in testflash. . . . . . . . . . . 17

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ST92F120/F124/150/F250 TESTFLASH

2 OVERVIEW

The structure of the TestFlash content is shown by the following figure:

Figure 1. ST9 TestFlash content

230000h

230020h

230023h

230026h

230029h

23002Ch

23002Fh

230032h

230035h

230E80h

231E80h

231F78h

231F80h

231FFCh

Vector Table

Power-On

routine

Code Update routine (in-system programming)

SCI Interrupt

routines

E3TM Initialization

E3TM

Management

routines

E3TM Swap Error:

Find Wrong Pages

E3TM Swap Error:

Find Wrong Bytes in given Page

E3TM Swap Error: Complete aborted Swap phase

E3TM Reset

to delivery status

Not Used

(4 Kbytes)

Reserved for Testing (248 bytes)

Otp area 124 bytes

Protections

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ST92F120/F124/150/F250 TESTFLASH

2.1 VECTOR TABLE

The first 16 words of the TestFlash contain the Vector Table.

The Power-On Vector is read when exiting from Reset. The Monitor Vector is read in Embedded Emulation Mode after an ETRAP instruction or an external Break. The NMI Vector is read if a Non Maskable Interrupt occurs. The SCI Interrupt Vectors are used for the In-System Programming routine.

Figure 2. Vector Table

Vector Table

	230000h	Power-On Vector
	230002h
		Monitor Vector
	230004h
		NMI Vector
	230006h
		Mask Set Number
	230008h
		Device Identifier
	23000Ah
		TestFlash Code Revision
	230010h
		SCI Error Vector
	230012h
		SCI Address Match Vector
	230014h
		SCI Receiving End Vector
	230016h
		SCI Transmitting End Vector

2.1.1 Device identifier

This identifier contains the information about the device, its flash size and its reset vector location.

2.1.2 Testflash code revision

The CheckSum is the sum of all the bytes from 230000h to 230E77h, it can be used to verify if the actual TestFlash content is the most recent one, or if the TestFlash content is corrupted.

			rev 2.6		rev 2.7		rev 2.7.1
	Flash	Device ID	TF rev	Testflash	TF rev	Testflash	TF rev	Testflash
Device			(23000		(23000		(23000
	size	(230008h)	Ah)	checksum	Ah)	checksum	Ah)	checksum
ST92F124/F150	64K	1024h	xx26h	933BFh	xx27h	8FC55h	0127h	8FBEBh
ST92F124/F150	128K	1080h	xx26h	9341Bh	xx27h	8FCB1h	0127h	8FC47h
ST92F250	256K	1100h	xx26h	9339Ch	xx27h	8FC32h	0127h	8FBC8h

2.2 USER OTP AREA

The 124 bytes of TestFlash from 231F80h to 231FFBh are available to the User application as One Time Programmable area (not erasable).

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ST92F120/F124/150/F250 TESTFLASH

2.3 PROTECTIONS

The TestFlash locations shown by the following figure have a special meaning related to the Access and Write Flash Protection features (refer to the datasheets).

Figure 3. Protection Map

	Protection
231FFCh	NVAPR
231FFDh	NVWPR
231FFEh	NVPWD0
231FFFh	NVPWD1

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ST92F120/F124/150/F250 TESTFLASH

3 ROUTINES DESCRIPTION

3.1 POWER-ON ROUTINE (230020H)

Inputs: None.

Outputs: R0, R1.

Variables: R2-R47, R160-R223 (for Stack).

Goal: to perform the initializations of ST9 device (Boot Code).

The Power-On routine is executed automatically when exiting reset.

The Power-On routine performs the following operations:

■initialize the Stack Pointer in the Register File (for this reason, this routine modifies the Registers of group A, B, C and D).

■call the “E3TM Initialization routine“ (230026h).

■initialize the MMU paged registers as shown by the following table.

Table 1. MMU Registers Initialization

Register	Value	Seg	Notes
DPR0 - R240	00h	0h	1st 16k-page
DPR1 - R241	01h	0h	2nd 16k-page
DPR2 - R242	02h	0h	3rd 16k-page
DPR3 - R243	80h	20h	1st 16k-page
ISR - R248	00h	0h
DMASR - R249	20h	20h
MPSR - R250	21h	21h
MDPR0 - R251	84h	21h	1st 32k-page
MDPR1 - R252	86h	21h	2nd 32k-page

■Set bit MEMSEL (bit 4) in the R246 (EMR2) register page 21

■Set the Register Page Pointer to page 0.

■Set Group 0 as working registers.

■Set Program Memory.

■read in 000000h the first word of segment 0h (Flash Memory), that is interpreted as the Power-On Vector of the User application. (Warning: if the device identifier is equal to 0080h, the User Reset Vector is read in 01E000h instead of in 000000h).

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