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Diffstat (limited to 'src/devices/cpu/m6502/m6500_1.cpp')
-rw-r--r--src/devices/cpu/m6502/m6500_1.cpp22
1 files changed, 11 insertions, 11 deletions
diff --git a/src/devices/cpu/m6502/m6500_1.cpp b/src/devices/cpu/m6502/m6500_1.cpp
index 6ba2f9c3919..8aa30f08c89 100644
--- a/src/devices/cpu/m6502/m6500_1.cpp
+++ b/src/devices/cpu/m6502/m6500_1.cpp
@@ -12,10 +12,10 @@
* Sixteen-bit programmable counter/latch
The onboad clock generator has mask options for an external crystal
- (2MHz to 6MHz) an external TTL-compatible clock with a 300Ω pull-up
+ (2MHz to 6MHz), an external TTL-compatible clock with a 300Ω pull-up
resistor (2MHz to 6MHz), or an RC oscillator with an external 47kΩ
resistor and internal capacitor (nominally 2MHz). The clock is
- divided by two to generate the two-phase CPU code clock.
+ divided by two to generate the two-phase CPU core clock.
There is no on-board power-on reset generator. The /RES pin must be
held low (asserted) for at least eight phase 2 clock cycles after
@@ -45,7 +45,7 @@
on the CNTR pin in event counter mode is half the phase 2 clock
rate. This suggests that an internal flag is set when a rasing edge
is detected on CNTR and reset when the counter is synchronously
- decremented. This is not emulated - for simplicity the counter is
+ decremented. This is not emulated - for simplicity, the counter is
asynchronously decremented on detecting a rising edge on CNTR.
The CNTR pin has an active low driver and internal passive pull-up.
@@ -59,14 +59,14 @@
is unknown what other differences these devices have.
TODO:
- - For some reason most if not all Amiga MCU programs accesses arbitrary
- zero page 0x90-0xff with a back-to-back cmp($00, x) opcode at
- PC=c06-c08 with the actual result discarded. X can be any value in
- the 0x90-0xff range, depending on the last user keypress row source
- e.g. 0xdf-0xe0 for 'A', 0xef-0xf0 for 'Q', 0xfb-0xfc for function
- keys.
- This can be extremely verbose in the logging facility so we currently
- nop it out for the time being.
+ - For some reason most if not all Amiga MCU programs access
+ arbitrary zero page 0x90-0xff with a back-to-back cmp($00, x)
+ opcode at PC=c06-c08 with the actual result discarded. X can be
+ any value in the 0x90-0xff range, depending on the last user
+ keypress row source e.g. 0xdf-0xe0 for 'A', 0xef-0xf0 for 'Q',
+ 0xfb-0xfc for function keys.
+ This can be extremely verbose in the logging facility so we nop it
+ out for the time being.
***************************************************************************/