Motor de Búsqueda de Datasheet de Componentes Electrónicos |
|
TSC80251G2D Datasheet(PDF) 9 Page - TEMIC Semiconductors |
|
TSC80251G2D Datasheet(HTML) 9 Page - TEMIC Semiconductors |
9 / 63 page Rev. A - May 7, 1999 9 TSC80251G2D 6. Address Spaces The TSC80251G2D derivatives implement four different address spaces: q On-chip ROM program/code memory (not present in ROMless devices) q On-chip RAM data memory q Special Function Registers (SFRs) q Configuration array 6.1 Program/Code Memory The TSC83251G2D and TSC87251G2D implement 32 Kbytes of on-chip program/code memory. Figure 5 shows the split of the internal and external program/code memory spaces. If EA# is tied to a high level, the 32-Kbyte on-chip program memory is mapped in the lower part of segment FF: where the C251 core jumps after reset. The rest of the program/code memory space is mapped to the external memory. If EA# is tied to a low level, the internal program/code memory is not used and all the accesses are directed to the external memory. The TSC83251G2D products provide the internal program/code memory in a masked ROM memory while the TSC87251G2D products provide it in an EPROM memory. For the TSC80251G2D products, there is no internal program/code memory and EA# must be tied to a low level. Figure 5. Program/Code Memory Mapping Notes: Special care should be taken when the Program Counter (PC) increments: 1. If the program executes exclusively from on-chip code memory (not from external memory), beware of executing code from the upper eight bytes of the on-chip ROM (FF:7FF8h-FF:7FFFh). Because of its pipeline capability, the TSC80251G2D derivative may attempt to prefetch code from external memory (at an address above FF:7FFFh) and thereby disrupt I/O Ports 0 and 2. Fetching code constants from these 8 bytes does not affect Ports 0 and 2. 2. When PC reaches the end of segment FF:, it loops to the reset address FF:0000h (for compatibility with the C51 Architecture). When PC increments beyond the end of segment FE:, it continues at the reset address FF:0000h (linearity). When PC increments beyond the end of segment 01:, it loops to the beginning of segment 00: (this prevents from its going into the reserved area). On-chip ROM/EPROM Code Memory Program/code Segments Program/code External Memory Space 32 Kbytes EA#= 0 EA#= 1 32 Kbytes 32 Kbytes Reserved 64 Kbytes 128 Kbytes FF:FFFFh FF:8000h FF:7FFFh FF:0000h FE:FFFFh FE:0000h FD:FFFFh 01:FFFFh 01:0000h 02:0000h 00:FFFFh 00:0000h |
Número de pieza similar - TSC80251G2D |
|
Descripción similar - TSC80251G2D |
|
|
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 |