Motorola MPC860 PowerQUICC, Руководство пользователя

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MOTOROLA Chapter 16. Memory Controller 16-37
Part IV. Hardware Interface
6 BST2 Byte-select timing 2. DeÞnes the state of BS during clock phase 3.
0 Asserted at the rising edge of GCLK2_50.
1 Negated at the rising edge of GCLK2_50
The Þnal value of the BS lines depends on the values of BRx[PS], the TSIZ lines, and A[30Ð31] for
the access. See Section 16.6.4.3, ÒByte-Select Signals (BxTx).Ó
7 BST3 Byte-select timing 3. DeÞnes the state of BS during clock phase 4.
0 Asserted at the falling edge of GCLK1_50.
1 Negated at the falling edge of GCLK1_50.
The Þnal value of the BS lines depends on the values of BRx[PS], the TSIZ lines, and A[30Ð31] for
the access. See Section 16.6.4.3, ÒByte-Select Signals (BxTx).Ó
8Ð9 G0L General-purpose line 0 lower. DeÞnes the state of GPL0 during phases 1Ð3.
10 Asserted at the falling edge of GCLK2_50.
11 Negated at the falling edge of GCLK2_50.
00 Driven at the falling edge of GCLK2_50 with an address signal as deÞned in M
x MR[G0CL x ].
10Ð11 G0H General-purpose line 0 higher. DeÞnes the state of GPL0 during phase 4.
10 Asserted at the falling edge of GCLK1_50.
11 Negated at the falling edge of GCLK1_50.
00 Driven at the falling edge of GCLK1_50 with an address signal as deÞned in M
x MR[G0CL x ].
12 G1T4 General-purpose line 1 timing 4. DeÞnes the state of GPL1 during phase 1Ð3.
0 Asserted at the falling edge of GCLK2_50.
1 Negated at the falling edge of GCLK2_50.
13 G1T3 General-purpose line 1 timing 3. DeÞnes the state of GPL1 during phase 4.
0 Asserted at the falling edge of GCLK1_50.
1Negated at the falling edge of GCLK1_50.
14 G2T4 General-purpose line 2 timing 4. DeÞnes the state of GPL2 during phase 1Ð3.
0 Asserted at the falling edge of GCLK2_50.
1 Negated at the falling edge of GCLK2_50.
15 G2T3 General-purpose line 2 timing 3. DeÞnes the state of GPL2 during phase 4.
0 Asserted at the falling edge of GCLK1_50.
1 Negated at the falling edge of GCLK1_50.
16 G3T4 General-purpose line 3 timing 4. DeÞnes the state of GPL3 during phase 1Ð3.
0 Asserted at the falling edge of GCLK2_50.
1Negated at the falling edge of GCLK2_50.
17 G3T3 General-purpose line 3 timing 3. DeÞnes the state of GPL3 during phase 4.
0 Asserted at the falling edge of GCLK1_50.
1Negated at the falling edge of GCLK1_50.
18 G4T4/
DLT3 General-purpose line 4 timing 4/delay time 3. The function is determined by M x MR[GPL x 4DIS].
G4T4 If M x MR deÞnes UPWAITx/GPL_x4 as an output (GPL_x4), this bit functions as G4T4:
0 The value of GPL4 at the falling edge of GCLK2_50 will be 0.
1 The value of GPL4 at the falling edge of GCLK2_50 will be 1.
DLT3 If M x MR[GPL x 4DIS] = 1, UPWAITx is chosen and this bit functions as DLT3.
0 The data bus should be sampled at the rising edge of GCLK2_50 for a read in this cycle.
1 The data bus should be sampled at the falling edge of GCLK2_50 for a read in this cycle.
Table 16-13. RAM Word Bit Settings (Continued)
Bit Name Description