Differences

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--- programmable_bitmap_sequencer [2022/07/14 15:20] – [Principles of operation] silverdr
+++ programmable_bitmap_sequencer [2022/07/14 15:23] (current) – [Principles of operation] silverdr
@@ Line 38: / Line 38: @@
 Once PBS decides to act, it performs following operations in every cycle:
-  - It uses an internal copy of ''S_BASE'' register to determine where to fetch the graphics data from. ''S_BASE'' is a 16-bit register, so the addressable memory is 64KiB - one memory bank. Which of the eight memory banks is used is controlled by bits ''S_RAMBANK'' in register ''PBS_CONTROL'' (''$40:210'').
+  - It uses an internal copy of ''S_BASE'' register to determine where to fetch graphics data from. ''S_BASE'' is a 16-bit register, so the addressable memory is 64KiB - one memory bank. Which of the eight memory banks is used is controlled by bits ''S_RAMBANK'' in register ''PBS_CONTROL'' (''$40:210'').
-  - Once the byte is fetched, VASYL can do some simple bit operations on it (see below), then writes it to the VIC-II data bus.
+  - Once graphics data byte is fetched, VASYL can do some simple bitwise operations on it (see below), then writes it to the VIC-II data bus.
   - Finally, the internal copy of ''S_BASE'' is incremented by ''S_STEP'', yielding the address of a byte to use in the next cycle. With a typically organized graphics data, this value is equal to 1.