| ??? 09/28/05 15:14 Read: times |
#101671 - ERAM Responding to: ???'s previous message |
I went to the "mother of 8051" - Intel - and downloaded the available documents on what I think is the first derivative adding the "internal XRAM" - the 8XC51RA/RB/RC (somebody can correct me if I am wrong).
8XC51RA/RB/RC
Hardware Description (27266801.pdf) said:
The C51RX has internal data memory that is mapped into four separate segments: the lower 128 bytes of RAM, upper 128 bytes of RAM, 128 bytes special function register (SFR) and 256 bytes expanded RAM (ERAM). The four segments are: 1. The Lower 128 bytes of RAM (addresses 00H to 7FH) are directly and indirectly addressable 2. The Upper 128 bytes of RAM (addresses 80H to FFH) are indirectly addressable only 3. The Special Function Registers SFRs (addresses 80H to FFH) are directly addressable only 4. The 256-bytes expanded RAM (ERAM 00H–FFH) are indirectly accessed by move external instruction MOVX and with the EXTRAM bit cleared So it seems the correct abbreviation for "internal XRAM" is ERAM... Jan Waclawek |
| Topic | Author | Date |
| glossary | 01/01/70 00:00 | |
| Dunno, but... | 01/01/70 00:00 | |
| glossary | 01/01/70 00:00 | |
| "external" | 01/01/70 00:00 | |
| explain | 01/01/70 00:00 | |
| indirect? | 01/01/70 00:00 | |
| Flash | 01/01/70 00:00 | |
| XRAM | 01/01/70 00:00 | |
| X? | 01/01/70 00:00 | |
| XRAM | 01/01/70 00:00 | |
| MOVX is the key | 01/01/70 00:00 | |
| access | 01/01/70 00:00 | |
| Sort of | 01/01/70 00:00 | |
| wikish | 01/01/70 00:00 | |
| memory types and datatypes | 01/01/70 00:00 | |
| precise | 01/01/70 00:00 | |
| maybe like this | 01/01/70 00:00 | |
| XDATA | 01/01/70 00:00 | |
| re: XDATA | 01/01/70 00:00 | |
| update | 01/01/70 00:00 | |
| why? does anyone ever look there | 01/01/70 00:00 | |
| We don't understand each other | 01/01/70 00:00 | |
| My understanding of the wiki was that it | 01/01/70 00:00 | |
| wicked | 01/01/70 00:00 | |
| re chip directories | 01/01/70 00:00 | |
| Hang on | 01/01/70 00:00 | |
| sorry | 01/01/70 00:00 | |
| Nope | 01/01/70 00:00 | |
Congrats Steve. | 01/01/70 00:00 | |
| stack =? IDATA | 01/01/70 00:00 | |
| PDATA??? | 01/01/70 00:00 | |
| PDATA | 01/01/70 00:00 | |
| That's the crux | 01/01/70 00:00 | |
| internal external | 01/01/70 00:00 | |
| Is there is difference in... | 01/01/70 00:00 | |
| external vs internal XRAM | 01/01/70 00:00 | |
| or other sfr | 01/01/70 00:00 | |
| ERAM | 01/01/70 00:00 | |
| Wiki Wiki | 01/01/70 00:00 | |
| glossary on wiki | 01/01/70 00:00 |