Transtech Transputer, User Manual

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The Host Interface
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Transputer Motherboard User Manual TMB M 711
to all locations between #9000 and #BFFF. Table 52 shows the
bit allocations.
• The transputer has 32KBytes of its memory space mapped to the
PC’s I/O space. The actual mapping depends on whether the
transputer is reading or writing to the memory space.
• The base address of the registers in the PC’s I/O space can be
set to #150 (default) or #200.
• The PC’s I/O space contains registers for DMA & IRQ for
compatibility with the B008 style of interface. The TMB16
supports DMA channel 1 and IRQ channels 3 (default) & 7.
• Writing to the mode register in the PC’s I/O space determines
whether the TMB16 works in full 16bit mode (bit0 set to 0) or
B004/B008 compatibility mode (bit0 set to 1). Note that the
address of the mode register is either 14 or 17, depending on the
contents of the board ID register (see below).
• Reading from the board ID register (base a 0x11) returns
a value as follows
Bit Function
0 Data ready to send
1 Data ready to receive
2 1
⇒
Byte mode, 0
⇒
string mode
Table 52: TMB16 Flags register
Bit Function
0 Processor type: 0
⇒
T222, 1
⇒
T225
1 Mode reg. offset: 0
⇒
0x14, 1
⇒
ox17
2, 3 Reserved: read as 0
4-7 Undefined
Table 53: TMB16 Board ID register