BPLCON4

 +------+----------+----------------------------------------------------------+
 | BIT# | BPLCON4  | DESCRIPTION                                              |
 +------+----------+----------------------------------------------------------+
 | 15   | BPLAM7=0 | This 8 bit field is XOR`ed with the 8 bit plane color    |
 |      |          | address, thereby altering the color address sent to the  |
 |      |          | color table (x=1-8)                                      |
 | 14   | BPLAM6=0 |                                                          |
 | 13   | BPLAM5=0 |                                                          |
 | 12   | BPLAM4=0 |                                                          |
 | 11   | BPLAM3=0 |                                                          |
 | 10   | BPLAM2=0 |                                                          |
 | 09   | BPLAM1=0 |                                                          |
 | 08   | BPLAM0=0 |                                                          |
 | 07   | ESPRM7=0 | 4 Bit field provides the 4 high order color table address|
 |      |          | bits for even sprites: SPR0,SPR2,SPR4,SPR6. Default value|
 |      |          | is 0001 binary. (x=7-4)                                  |
 | 06   | ESPRM6=0 |                                                          |
 | 05   | ESPRM5=0 |                                                          |
 | 04   | ESPRM4=1 |                                                          |
 | 03   | OSPRM7=0 | 4 Bit field provides the 4 high order color table address|
 |      |          | bits for odd sprites: SPR1,SPR3,SPR5,SPR7. Default value |
 |      |          | is 0001 binary. (x=7-4)                                  |
 | 02   | OSPRM6=0 |                                                          |
 | 01   | OSPRM5=0 |                                                          |
 | 00   | OSPRM4=1 |                                                          |
 +------+----------+----------------------------------------------------------+
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