CHANNEL_MAP
lc = CHANNEL_MAP(mapper, channel, write);
if ((CHANNEL_MAP(mc_channel_mapper, i, 0) & c) != 0) {
if ((CHANNEL_MAP(mc_channel_mapper, i, 1) & c) != 0) {
if (CHANNEL_MAP(mc_channel_mapping, 2, 0) == 0 &&
CHANNEL_MAP(mc_channel_mapping, 2, 1) == 0)