A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
1 | AMSTRAD CPC | 4 x 8 3.3V/5V Level Converters | Raspberry Pi B+, 28 pins | |||||||||||||||||||||||
2 | ||||||||||||||||||||||||||
3 | CPC BUS | PIN # | CPC Connections | 5V | 3.3V | PI Connections | PIN # | PI BUS | ||||||||||||||||||
4 | ||||||||||||||||||||||||||
5 | ----- | Sound | 1 | Level Converter | #1 | |||||||||||||||||||||
6 | Key | |||||||||||||||||||||||||
7 | Address Bus | A15 | 3 | ---> | 1.B7 | 1.B7 | <---> | 1.A7 | 1.A7 | ---> | 26 | BCM 7 | Power | (same on Spectrum, MSX, PCW, SC3000) | ||||||||||||
8 | " | A14 | 4 | ---> | 1.B6 | 1.B6 | <---> | 1.A6 | 1.A6 | ---> | 31 | BCM 6 | Address Bus | (same on Spectrum, MSX, PCW, SC3000) | ||||||||||||
9 | " | A13 | 5 | ---> | 1.B5 | 1.B5 | <---> | 1.A5 | 1.A5 | ---> | 29 | BCM 5 | Data Bus | (same on Spectrum, MSX, PCW, SC3000) | ||||||||||||
10 | " | A12 | 6 | ---> | 1.B4 | 1.B4 | <---> | 1.A4 | 1.A4 | ---> | 7 | BCM 4 | Control I/O | |||||||||||||
11 | " | A11 | 7 | ---> | 1.B3 | 1.B3 | <---> | 1.A3 | 1.A3 | ---> | 5 | BCM 3 | ||||||||||||||
12 | " | A10 | 8 | ---> | 1.B2 | 1.B2 | <---> | 1.A2 | 1.A2 | ---> | 3 | BCM 2 | PI Not Connected | |||||||||||||
13 | " | A9 | 9 | ---> | 1.B1 | 1.B1 | <---> | 1.A1 | 1.A1 | ---> | 28 | BCM 1 | 2 | 5V Power | ||||||||||||
14 | " | A8 | 10 | ---> | 1.B0 | 1.B0 | <---> | 1.A0 | 1.A0 | ---> | 27 | BCM 0 | 4 | 5V Power | ||||||||||||
15 | 5 Volts | VCC | 27 | ---> | 1.VCCB, 2.VCCB, 3.VCCB, 4.VCCB | 1.VCCB | <---> | 1.VCCA | 1.VCCA, 2.VCCA | <--- | 1 | Power 3.3V | 9 | Ground | ||||||||||||
16 | Ground | GND | 2 | ---> | 1.GND, 2.GND | 1.GND | <---> | 1.GND | 1.GND | <--- | 6 | Ground | 20 | Ground | ||||||||||||
17 | 30 | Ground | ||||||||||||||||||||||||
18 | Level Converter | #2 | 39 | Ground | ||||||||||||||||||||||
19 | ||||||||||||||||||||||||||
20 | " | A7 | 11 | ---> | 2.B6 | 2.B7 | <---> | 2.A7 | 2.B7 | ---> | 10 | BCM 15 | CPC Not Connected | |||||||||||||
21 | " | A6 | 12 | ---> | 2.B6 | 2.B6 | <---> | 2.A6 | 2.A6 | ---> | 8 | BCM 14 | 1 | Sound | ||||||||||||
22 | " | A5 | 13 | ---> | 2.B5 | 2.B5 | <---> | 2.A5 | 2.A5 | ---> | 33 | BCM 13 | 29 | M1 | ||||||||||||
23 | " | A4 | 14 | ---> | 2.B4 | 2.B4 | <---> | 2.A4 | 2.A4 | ---> | 32 | BCM 12 | 30 | RFSH | ||||||||||||
24 | " | A3 | 15 | ---> | 2.B3 | 2.B3 | <---> | 2.A3 | 2.A3 | ---> | 23 | BCM 11 | 34 | HALT | ||||||||||||
25 | " | A2 | 16 | ---> | 2.B2 | 2.B2 | <---> | 2.A2 | 2.A2 | ---> | 19 | BCM 10 | 35 | INT | ||||||||||||
26 | " | A1 | 17 | ---> | 2.B1 | 2.B1 | <---> | 2.A1 | 2.A1 | ---> | 21 | BCM 9 | 31 | IORQ | ||||||||||||
27 | " | A0 | 18 | ---> | 2.B0 | 2.B0 | <---> | 2.A0 | 2.A0 | ---> | 24 | BCM 8 | 36 | NMI | ||||||||||||
28 | 5 Volts | VCC | 27 | ---> | 1.VCCB, 2.VCCB, 3.VCCB, 4.VCCB | 2.VCCB | <---> | 2.VCCA | 1.VCCA, 2.VCCA | <--- | 1 | Power 3.3V | 37 | BUSRQ | ||||||||||||
29 | Ground | GND | 2 | ---> | 1.GND, 2.GND | 2.GND | <---> | 2.GND | 2.GND | <--- | 14 | Ground | 38 | BUSAK | ||||||||||||
30 | 39 | READY | ||||||||||||||||||||||||
31 | Level Converter | #3 | 41 | RSET | ||||||||||||||||||||||
32 | 44 | RAMRD | ||||||||||||||||||||||||
33 | Data Bus | D7 | 19 | <--> | 3.B7 | 3.B7 | <---> | 3.A7 | 3.A7 | <--> | 16 | BCM 23 | 46 | CURSOR | ||||||||||||
34 | " | D6 | 20 | <--> | 3.B6 | 3.B6 | <---> | 3.A6 | 3.A6 | <--> | 15 | BCM 22 | 47 | LPEN | ||||||||||||
35 | " | D5 | 21 | <--> | 3.B5 | 3.B5 | <---> | 3.A5 | 3.A5 | <--> | 40 | BCM 21 | 48 | EXP | ||||||||||||
36 | " | D4 | 22 | <--> | 3.B4 | 3.B4 | <---> | 3.A4 | 3.A4 | <--> | 38 | BCM 20 | 50 | CLK | ||||||||||||
37 | " | D3 | 23 | <--> | 3.B3 | 3.B3 | <---> | 3.A3 | 3.A3 | <--> | 35 | BCM 19 | ||||||||||||||
38 | " | D2 | 24 | <--> | 3.B2 | 3.B2 | <---> | 3.A2 | 3.A2 | <--> | 12 | BCM 18 | ||||||||||||||
39 | " | D1 | 25 | <--> | 3.B1 | 3.B1 | <---> | 3.A1 | 3.A1 | <--> | 11 | BCM 17 | ||||||||||||||
40 | " | D0 | 26 | <--> | 3.B0 | 3.B0 | <---> | 3.A0 | 3.A0 | <--> | 36 | BCM 16 | ||||||||||||||
41 | 5 Volts | VCC | 27 | ---> | 1.VCCB, 2.VCCB, 3.VCCB, 4.VCCB | 3.VCCB | <---> | 3.VCCA | 3.VCCA, 4.VCCA | <--- | 17 | Power 3.3V | ||||||||||||||
42 | Ground | GND | 49 | ---> | 3.GND, 4.GND | 3.GND | <---> | 3.GND | 3.GND | <--- | 25 | Ground | ||||||||||||||
43 | ||||||||||||||||||||||||||
44 | Level Converter | #4 | ||||||||||||||||||||||||
45 | ||||||||||||||||||||||||||
46 | When /MREQ="0" the CPU is performing a memory operation. A15-A0 contain the memory address. | Memory Request | MREQ | 28 | ---> | 4.B0 | 4.B0 | <---> | 4.A0 | 4.A0 | ---> | 18 | BCM 24 | to CPC MREQ | (same on Spectrum, MSX, PCW, SC3000) | |||||||||||
47 | /M1 (Machine cycle one; Output from CPU). When /M1="0" there are two possible functions: Interrupt acknowledge: /IORQ="0" CPU is fetching the op-code part of an instruction: /MREQ="0" and /IORQ="1" | Machine Cycle1 | M1 | 29 | ||||||||||||||||||||||
48 | ----- | RFSH | 30 | |||||||||||||||||||||||
49 | When /IORQ="0" the CPU is performing a I/O operation. A15-A0 contain the I/O address. | I/O Request | IORQ | 31 | ||||||||||||||||||||||
50 | If /RD is "0" then the operation is reading from memory. D7-D0 will contain data read from the memory. | Read | RD | 32 | ---> | 4.B1 | 4.B1 | <---> | 4.A1 | 4.A1 | ---> | 22 | BCM 25 | to CPC RD | (same on Spectrum, MSX, PCW, SC3000) | |||||||||||
51 | If /WR is "0" then the operation is writing to memory. D7-D0 contain data to write to the memory. | Write | WR | 33 | ---> | 4.B2 | 4.B2 | <---> | 4.A2 | 4.A2 | ---> | 37 | BCM 26 | to CPC WR | (same on Spectrum, MSX, PCW, SC3000) | |||||||||||
52 | ----- | HALT | 34 | |||||||||||||||||||||||
53 | ----- | INT | 35 | |||||||||||||||||||||||
54 | ----- | NMI | 36 | |||||||||||||||||||||||
55 | ? | Bus Request | BUSRQ | 37 | ||||||||||||||||||||||
56 | When /BUSAK="0" the CPU is signalling that control of the address bus, data bus and output signals has been released, and the device can take control. | Bus Acknowledge | BUSAK | 38 | ||||||||||||||||||||||
57 | ? | ----- | READY | 39 | ||||||||||||||||||||||
58 | /BUS RESET (Bus Reset; Input to PIO/CPU) Acts similarly to /RESET but also resets the PIO chip. | ----- | BRST | 40 | <--- | 4.B4 | 4.B4 | <---> | 4.A4 | 4.A4 | <--- | 24 | BCM 8 | to CPC BRST | (to RESET on Spectrum & MSX, do NOT connect to PCW, SC3000) | |||||||||||
59 | /RESET (Reset; Input to CPU). When /RESET="0" the CPU is held in the reset state. When the reset state is released, the CPU Program Counter (PC) is set to "0" and execution begins resumes from the new PC address. | ----- | RSET | 41 | note: perhaps put a LED when online since PCW cannot control reset | |||||||||||||||||||||
60 | /ROMEN (ROM Enable; Output from Gate-Array). When /ROMEN="0" a ROM read operation is active. This signal is generated by the Gate-Array. This signal will be "0" when: A15=A14="0" and bit 2 of the Gate-Array ROM configuration register is set to 0, (lower ROM enable) A15=A14="1" and bit 3 of the Gate-Array ROM configuration register is set to 0. (upper ROM enable) A expansion device (e.g. a ROM-board) can use this signal to activate the selected ROM plugged into the device. | ROM Enable | ROMEN | 42 | note: for computers that don't have reset inputs, PI can reset via software | |||||||||||||||||||||
61 | ROMDIS (Internal ROM Disable; Input to internal ROM). When ROMDIS="1" the internal ROM of the CPC/CPC+/KC Compact is forced inactive. e.g. a ROM-board device would use this signal to override the ROM selection with a ROM plugged into the device. The internal ROM would be forced inactive, and the selected expansion ROM would be activated. | ROM Disable | ROMDIS | 43 | ||||||||||||||||||||||
62 | When /RAMRD="0" a ram read operation is active. This signal is generated by the Gate-Array. This signal will be "0" when: A15=A14="0" and bit 2 of the Gate-Array ROM configuration register is set to 1. (lower ROM disable) A15=A14="1" and bit 3 of the Gate-Array ROM configuration register is set to 1. (upper ROM disable) A15 is not equal to A14. | RAM Read | RAMRD | 44 | ||||||||||||||||||||||
63 | When RAMDIS="1" the internal RAM of the CPC/CPC+/KC Compact is forced inactive. e.g. a ram-expansion device would use this signal to override the internal RAM selection with the ram on the device. The internal RAM would be forced inactive, and the ram on the ram-expansion would be actived. | RAM Disable | RAMDIS | 45 | <--- | 4.B3 | 4.B3 | <---> | 4.A3 | 4.A3 | <--- | 13 | BCM 27 | to CPC RAMDIS | (to ROMCS on Spectrum, CSRAM on SC3000, -->CS1 or -->CS2 for MSX. Do I need BUSDIR for MSX?) | |||||||||||
64 | ----- | CURSOR | 46 | |||||||||||||||||||||||
65 | ----- | LPEN | 47 | |||||||||||||||||||||||
66 | 5 Volts | VCC | 27 | ---> | 1.VCCB, 2.VCCB, 3.VCCB, 4.VCCB | 4.VCCB | <---> | 4.VCCA | 3.VCCA, 4.VCCA | <--- | 17 | Power 3.3V | ||||||||||||||
67 | ----- | EXP | 48 | |||||||||||||||||||||||
68 | Ground | GND | 49 | ---> | 3.GND, 4.GND | 4.GND | <---> | 4.GND | 4.GND | <--- | 34 | Ground | ||||||||||||||
69 | 4MHz Clock | 4Mhz Clock | CLK | 50 | ||||||||||||||||||||||
70 | ||||||||||||||||||||||||||
71 | ||||||||||||||||||||||||||
72 | ||||||||||||||||||||||||||
73 |