Read Reg is ter - Con ver sion Status
D7 - N/A
D6 - N/A
D5 - N/A
D4 - N/A
D3 - N/A
D2 - N/A
D1 - Busy 0 = Con verter busy, 1 = Con ver sion com plete
D0 - In ter rupt 0 = Con ver sion in prog ress, 1 = Con ver sion com plete
This status reg is ter in di cates when a con ver sion is com plete. It is rec om mended that
soft ware rou tines wait un til both the Con ver sion com plete and the In ter rupt bits are both
set bef ore read ing the con ver sion data.
3.1.2
Base + 1 Address
Write Reg is ter - Se lect Chan nel/Start Con ver sion
D7 - N/A
D6 - N/A
D5 - N/A
D4 - N/A
D3 - Bit 3 of se lect nib ble
D2 - Bit 2 of Se lect nib ble
D1 - Bit 1 of se lect nib ble
D0 - Bit 0 of se lect nib ble
Writ ing a value to the BASE + 1 I/O ad dress not only se lects the chan nel number as en -
coded in bits 3-0 but af ter a hard ware set tling de lay of ap proxi mately 6uS starts a con ver -
sion. This is the nor mal method to be gin a con ver sion as the chan nel se lec tion and
con ver sion start are auto mated into a sin gle write.
Read Reg is ter - LSB Data
D7 - D7 of con ver sion data
D6 - D6 “ ” “
D5 - D5 “ ” “
D4 - D4 “ ” “
D3 - D3 “ ” “
D2 - D2 “ ” “
D1 - D1 “ ” “
D0 - D0 “ ” “
Read ing of I/O base ad dress + 1 will pres ent the lower 8- bits of the 16- bit con ver sion
data. Note that on the 12- Bit con verter mod ule, the lower 4 bits of this reg is ter will al ways
read as 0. This al lows soft ware to trans par ently use ei ther the 12- bit or the 16- bit mod ule.
Page 3-2
PCM-A/D-12/16 OPERATIONS MANUAL
970513
WinSystems - "The Embedded Systems Authority"
Содержание PCM-A/D-12
Страница 22: ...4 APPENDIX A PCM A D Parts Placement Guide...
Страница 23: ...5 APPENDIX B PCM A D Parts List...
Страница 26: ...6 APPENDIX C BURR BROWN ADS7806 ADS7807 Datasheet Reprint...
Страница 64: ...7 APPENDIX D PCM A D Demo Software Source Listing...
Страница 73: ...8 APPENDIX E PCM A D Schematic Diagrams...