Electronic Components Datasheet Search |
|
ST6228CM6 Datasheet(PDF) 8 Page - STMicroelectronics |
|
ST6228CM6 Datasheet(HTML) 8 Page - STMicroelectronics |
8 / 84 page 8/84 ST62T28C/E28C MEMORY MAP (Cont’d) Table 1. ST62E28C/T28C Program Memory Map Note: OTP/EPROM devices can be programmed with the development tools available from STMicro- electronics (ST62E3X-EPB or ST623X-KIT). 1.3.2.1 Program ROM Page Register (PRPR) The PRPR register can be addressed like a RAM location in the Data Space at the address CAh; nevertheless it is a write only register that cannot be accessed with single-bit operations. This regis- ter is used to select the 2-Kbyte ROM bank of the Program Space that will be addressed. The number of the page has to be loaded in the PRPR register. Refer to the Program Space description for additional information concerning the use of this register. The PRPR register is not modified when an interrupt or a subroutine occurs. Care is required when handling the PRPR register as it is write only. For this reason, it is not allowed to change the PRPR contents while executing in- terrupt service routine, as the service routine cannot save and then restore its previous content. This operation may be necessary if common rou- tines and interrupt service routines take more than 2K bytes; in this case it could be necessary to di- vide the interrupt service routine into a (minor) part in the static page (start and end) and to a second (major) part in one of the dynamic pages. If it is im- possible to avoid the writing of this register in inter- rupt service routines, an image of this register must be saved in a RAM location, and each time the program writes to the PRPR it must write also to the image register. The image register must be written before PRPR, so if an interrupt occurs be- tween the two instructions the PRPR is not af- fected. Program ROM Page Register (PRPR) Address: CAh — Write Only Bits 2-7= Not used. Bit 5-0 = PRPR1-PRPR0: Program ROM Select. These two bits select the corresponding page to be addressed in the lower part of the 4K program address space as specified in Table 2. This register is undefined on Reset. Neither read nor single bit instructions may be used to address this register. Table 2. 6Kbytes Program ROM Page Register Coding 1.3.2.2 Program Memory Protection The Program Memory in OTP or EPROM devices can be protected against external readout of mem- ory by selecting the READOUT PROTECTION op- tion in the option byte. In the EPROM parts, READOUT PROTECTION option can be disactivated only by U.V. erasure that also results into the whole EPROM context erasure. Note: Once the Readout Protection is activated, it is no longer possible, even for STMicroelectronics, to gain access to the Program memory contents. Returned parts with a protection set can therefore not be accepted. ROM Page Device Address Description Page 0 0000h-007Fh 0080h-07FFh Reserved User ROM Page 1 “STATIC” 0800h-0F9Fh 0FA0h-0FEFh 0FF0h-0FF7h 0FF8h-0FFBh 0FFCh-0FFDh 0FFEh-0FFFh User ROM Reserved Interrupt Vectors Reserved NMI Vector Reset Vector Page 2 0000h-000Fh 0010h-07FFh Reserved User ROM Page 3 0000h-000Fh 0010h-07FFh Reserved User ROM 70 - - - - - - PRPR1 PRPR0 PRPR1 PRPR0 PC bit 11 Memory Page X X 1 Static Page (Page 1) 0 0 0 Page 0 0 1 0 Page 1 (Static Page) 1 0 0 Page 2 1 1 0 Page 3 8 |
Similar Part No. - ST6228CM6 |
|
Similar Description - ST6228CM6 |
|
|
Link URL |
Privacy Policy |
ALLDATASHEET.COM |
Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Datasheet Upload | Contact us | Privacy Policy | Link Exchange | Manufacturer List All Rights Reserved©Alldatasheet.com |
Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
Family Site : ic2ic.com |
icmetro.com |