Changes
/* Technical */
bit7-6 unknown/unused (maybe SPED related?)
bit5-0 allophone number
* [[SP0256]]
* [[SP0256 Voice Generator]]
* [[SP0256 Instruction Set]]
* [[SP0256 Allophones]]
* [[SP0256 Pin-Outs]]
The clock frequency (passed to the speech chip) is variable (can be changed
