diff --git a/rom/README.txt b/rom/README.txt
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+General Sound ROM v1.05b
+https://github.com/psbhlw/gs-firmware
+
+gs105b.32K.rom - for 27C256
+gs105b.64K.rom - for 27C512
+
+Both versions are identical in terms of functionality.
diff --git a/rom/gs105a.32K.rom b/rom/gs105b.32K.rom
similarity index 93%
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diff --git a/rom/gs105a.64K.rom b/rom/gs105b.64K.rom
similarity index 93%
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rename to rom/gs105b.64K.rom
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