tmk
11 jaren geleden
1 gewijzigde bestanden met toevoegingen van 39 en 15 verwijderingen
+ 39
- 15
protocol/adb.c
Bestand weergeven
| @@ -199,24 +199,48 @@ static inline bool read_bit(void) | |||
| { | |||
| // ADB Bit Cells | |||
| // | |||
| // bit0: ______~~~ | |||
| // 65 :35us | |||
| // bit cell time: 70-130us | |||
| // low part of bit0: 60-70% of bit cell | |||
| // low part of bit1: 30-40% of bit cell | |||
| // | |||
| // bit1: ___~~~~~~ | |||
| // 35 :65us | |||
| // bit cell time 70us 130us | |||
| // -------------------------------------------- | |||
| // low part of bit0 42-49 78-91 | |||
| // high part of bit0 21-28 39-52 | |||
| // low part of bit1 21-28 39-52 | |||
| // high part of bit1 42-49 78-91 | |||
| // | |||
| // bit0 low time: 60-70% of bit cell(42-91us) | |||
| // bit1 low time: 30-40% of bit cell(21-52us) | |||
| // bit cell time: 70-130us | |||
| // [from Apple IIgs Hardware Reference Second Edition] | |||
| // | |||
| // After 55us if data line is low/high then bit is 0/1. | |||
| // Too simple to rely on? | |||
| // bit0: | |||
| // 70us bit cell: | |||
| // ____________~~~~~~ | |||
| // 42-49 21-28 | |||
| // | |||
| // 130us bit cell: | |||
| // ____________~~~~~~ | |||
| // 78-91 39-52 | |||
| // | |||
| // bit1: | |||
| // 70us bit cell: | |||
| // ______~~~~~~~~~~~~ | |||
| // 21-28 42-49 | |||
| // | |||
| // 130us bit cell: | |||
| // ______~~~~~~~~~~~~ | |||
| // 39-52 78-91 | |||
| // | |||
| // read: | |||
| // ________|~~~~~~~~~ | |||
| // 55us | |||
| // Read data line after 55us. If data line is low/high then bit is 0/1. | |||
| // This method might not work at <90us bit cell time. | |||
| // | |||
| // [from Apple IIgs Hardware Reference Second Edition] | |||
| bool bit; | |||
| wait_data_lo(75); // wait the beginning of bit cell | |||
| wait_data_lo(75); // wait the start of bit cell at least 130ms(55+0+75) | |||
| _delay_us(55); | |||
| bit = data_in(); | |||
| wait_data_hi(36); // wait high part of bit cell | |||
| wait_data_hi(36); // wait high part of bit cell at least 91ms(55+36) | |||
| return bit; | |||
| } | |||
| @@ -258,7 +282,7 @@ Resources | |||
| --------- | |||
| ADB - The Untold Story: Space Aliens Ate My Mouse | |||
| http://developer.apple.com/legacy/mac/library/#technotes/hw/hw_01.html | |||
| Apple IIgs Hardware Reference Second Edition [p80(Chapter6 p121)] | |||
| Apple IIgs Hardware Reference Second Edition [Chapter6 p121] | |||
| ftp://ftp.apple.asimov.net/pub/apple_II/documentation/Apple%20IIgs%20Hardware%20Reference.pdf | |||
| ADB Keycode | |||
| http://72.0.193.250/Documentation/macppc/adbkeycodes/ | |||
| @@ -376,9 +400,9 @@ Communication | |||
| Global reset: | |||
| Host asserts low in 2.8-5.2ms. All devices are forced to reset. | |||
| Send request from device(Srq): | |||
| Service request from device(Srq): | |||
| Device can request to send at commad(Global only?) stop bit. | |||
| keep low for 300us to request. | |||
| Requesting device keeps low for 140-260us at stop bit of command. | |||
| Keyboard Data(Register0) | |||