Hello all,
I'm getting very conflicting information between nocash's fullsnes.txt and Anomie's memmap.txt regarding the clock rate of some of the memory regions and internal registers. It seems like nearly every clock rate is different between the two.
Conflict Example 1: fullsnes states that WRAM is accessed at 3.58MHz (Fast) while memmap states that it's accessed at 2.68MHz (Slow).
Conflict Example 2: fullsnes states that Bus-B is accessed at 2.68MHz (Slow) while memmap states that it's accessed at 3.58MHz (Fast).
From doing some additional research online it would seem that memmap.txt is actually correct and fullsnes.txt is wrong. But I've found nocash's documentation to be very reliable and his is also much more recent than Anomie's, so I'm not sure what to think. Can anyone tell me which one is correct?
I'm getting very conflicting information between nocash's fullsnes.txt and Anomie's memmap.txt regarding the clock rate of some of the memory regions and internal registers. It seems like nearly every clock rate is different between the two.
Conflict Example 1: fullsnes states that WRAM is accessed at 3.58MHz (Fast) while memmap states that it's accessed at 2.68MHz (Slow).
Conflict Example 2: fullsnes states that Bus-B is accessed at 2.68MHz (Slow) while memmap states that it's accessed at 3.58MHz (Fast).
From doing some additional research online it would seem that memmap.txt is actually correct and fullsnes.txt is wrong. But I've found nocash's documentation to be very reliable and his is also much more recent than Anomie's, so I'm not sure what to think. Can anyone tell me which one is correct?
nocash fullsnes wrote:
Code:
System Area (banks 00h-3Fh and 80h-BFh)
Offset Content Speed
0000h-1FFFh Mirror of 7E0000h-7E1FFFh (first 8Kbyte of WRAM) 3.58MHz
2000h-20FFh Unused 2.68MHz
2100h-21FFh I/O Ports (B-Bus) 2.68MHz
2200h-3FFFh Unused 2.68MHz
4000h-41FFh I/O Ports (manual joypad access) 1.78MHz
4200h-5FFFh I/O Ports 2.68MHz
6000h-7FFFh Expansion 3.58MHz
Offset Content Speed
0000h-1FFFh Mirror of 7E0000h-7E1FFFh (first 8Kbyte of WRAM) 3.58MHz
2000h-20FFh Unused 2.68MHz
2100h-21FFh I/O Ports (B-Bus) 2.68MHz
2200h-3FFFh Unused 2.68MHz
4000h-41FFh I/O Ports (manual joypad access) 1.78MHz
4200h-5FFFh I/O Ports 2.68MHz
6000h-7FFFh Expansion 3.58MHz
Anomie memmap wrote:
Code:
Banks | Addresses | Speed | Mapping
---------+-------------+-------+---------
$00-$3F | $0000-$1FFF | Slow | Address Bus A + /WRAM (mirror $7E:0000-$1FFF)
| $2000-$20FF | Fast | Address Bus A
| $2100-$21FF | Fast | Address Bus B
| $2200-$3FFF | Fast | Address Bus A
| $4000-$41FF | XSlow | Internal CPU registers (see Note 1 below)
| $4200-$43FF | Fast | Internal CPU registers (see Note 1 below)
| $4400-$5FFF | Fast | Address Bus A
| $6000-$7FFF | Slow | Address Bus A
| $8000-$FFFF | Slow | Address Bus A + /CART
<...snip...>
---------+-------------+-------+---------
$00-$3F | $0000-$1FFF | Slow | Address Bus A + /WRAM (mirror $7E:0000-$1FFF)
| $2000-$20FF | Fast | Address Bus A
| $2100-$21FF | Fast | Address Bus B
| $2200-$3FFF | Fast | Address Bus A
| $4000-$41FF | XSlow | Internal CPU registers (see Note 1 below)
| $4200-$43FF | Fast | Internal CPU registers (see Note 1 below)
| $4400-$5FFF | Fast | Address Bus A
| $6000-$7FFF | Slow | Address Bus A
| $8000-$FFFF | Slow | Address Bus A + /CART
<...snip...>