Motor de Búsqueda de Datasheet de Componentes Electrónicos |
|
ADUC832BS Datasheet(PDF) 14 Page - Analog Devices |
|
ADUC832BS Datasheet(HTML) 14 Page - Analog Devices |
14 / 80 page REV. 0 –14– ADuC832 MEMORY ORGANIZATION The ADuC832 contains four different memory blocks: • 62 kBytes of On-Chip Flash/EE Program Memory • 4 kBytes of On-Chip Flash/EE Data Memory • 256 Bytes of General-Purpose RAM • 2 kBytes of Internal XRAM Flash/EE Program Memory The ADuC832 provides 62 kBytes of Flash/EE program memory to run user code. The user can choose to run code from this internal memory or from an external program memory. If the user applies power or resets the device while the EA pin is pulled low, the part will execute code from the external program space; otherwise the part defaults to code execution from its internal 62 kBytes of Flash/EE program memory. Unlike the ADuC812, where code execution can overflow from the internal code space to external code space once the PC becomes greater than 1FFFH, the ADuC832 does not support the rollover from F7FFH in internal code space to F800H in external code space. Instead the 2048 bytes between F800H and FFFFH will appear as NOP instructions to user code. This internal code space can be downloaded via the UART serial port while the device is in-circuit. 56 kBytes of the program memory can be reprogrammed during runtime; thus the code space can be upgraded in the field using a user defined protocol or it can be used as a data memory. This will be discussed in more detail in the Flash/EE Memory section. Flash/EE Data Memory 4 kBytes of Flash/EE data memory are available to the user and can be accessed indirectly via a group of control registers mapped into the Special Function Register (SFR) area. Access to the Flash/EE data memory is discussed in detail later as part of the Flash/EE Memory section. General-Purpose RAM The general-purpose RAM is divided into two separate memories, namely the upper and the lower 128 bytes of RAM. The lower 128 bytes of RAM can be accessed through direct or indirect addressing. The upper 128 bytes of RAM can only be accessed through indirect addressing as it shares the same address space as the SFR space, which can only be accessed through direct addressing. The lower 128 bytes of internal data memory are mapped as shown in Figure 2. The lowest 32 bytes are grouped into four banks of eight registers addressed as R0 through R7. The next 16 bytes (128 bits), locations 20H through 2FH above the register banks, form a block of directly addressable bit locations at bit addresses 00H through 7FH. The stack can be located anywhere in the internal memory address space, and the stack depth can be expanded up to 2048 bytes. Reset initializes the stack pointer to location 07H and increments it once before loading the stack to start from locations 08H which is also the first register (R0) of register bank 1. Thus, if one is going to use more than one register bank, the stack pointer should be initialized to an area of RAM not used for data storage. BIT-ADDRESSABLE (BIT ADDRESSES) FOUR BANKS OF EIGHT REGISTERS R0 R7 BANKS SELECTED VIA BITS IN PSW 11 10 01 00 07H 0FH 17H 1FH 2FH 7FH 00H 08H 10H 18H 20H RESET VALUE OF STACK POINTER 30H GENERAL-PURPOSE AREA Figure 2. Lower 128 Bytes of Internal Data Memory The ADuC832 contains 2048 bytes of internal XRAM, 1792 bytes of which can be configured to be used as an extended 11-bit stack pointer. By default, the stack will operate exactly like an 8052 in that it will roll over from FFH to 00H in the general-purpose RAM. On the ADuC832, however, it is possible (by setting CFG832.7) to enable the 11-bit extended stack pointer. In this case, the stack will roll over from FFH in RAM to 0100H in XRAM. The 11-bit stack pointer is visible in the SP and SPH SFRs. The SP SFR is located at 81H as with a standard 8052. The SPH SFR is located at B7H. The 3 LSBs of this SFR contain the three extra bits necessary to extend the 8-bit stack pointer into an 11-bit stack pointer. UPPER 1792 BYTES OF ON-CHIP XRAM (DATA + STACK FOR EXSP = 1, DATA ONLY FOR EXSP = 0) 256 BYTES OF ON-CHIP DATA RAM (DATA + STACK) LOWER 256 BYTES OF ON-CHIP XRAM (DATA ONLY) 00H FFH 00H 07FFH CFG832.7 = 0 CFG832.7 = 1 100H Figure 3. Extended Stack Pointer Operation |
Número de pieza similar - ADUC832BS |
|
Descripción similar - ADUC832BS |
|
|
Enlace URL |
Política de Privacidad |
ALLDATASHEET.ES |
¿ALLDATASHEET es útil para Ud.? [ DONATE ] |
Todo acerca de Alldatasheet | Publicidad | Contáctenos | Política de Privacidad | Intercambio de Enlaces | Lista de Fabricantes 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 |