README.txt ========== The MakerLisp machine is a portable, modular computer system, designed to recapture the feel of classic computing, with modern hardware. The machine centers on a 2" x 3.5" business card-sized CPU, which can be used stand-alone, or plugged in to a 2" x 8" main board, for expansion into a full computer system. A laser-cut wood enclosure holds a small keyboard, an LCD monitor, the circuit boards, and a prototyping area with a breadboard for electronics experimentation and development. The CPU is a Zilog eZ80 running at 50 MHz, with up to 16 Mb of zero-wait state RAM. A VGA display adapter provides an IBM PC-like color text-mode display. A USB Host Controller supports a USB keyboard and other USB communications. Data storage and interchange is accomplished by a micro-SD card supporting the FAT file system. All four of these circuit boards (shown on the web site's cover page) are new MakerLisp products, and will be available as part of the first product offering Contents ======== o ZDS-II Compiler Versions o Serial Console - UARTs - Serial Keyboard and VGA Display o LEDs and Buttons - LEDs - Buttons o Configurations - Common Configuration Notes - Configuration Subdirectories ZDS-II Compiler Versions ======================== Version 5.3.0 I verified compilation using 5.30 on June 2, 2019. To use this version, I had to make spurious modification to the implementation of gmtimer() to work around an internal compiler error. I have still not verified that are no errors in the compiled code. Other Versions If you use any version of ZDS-II other than 5.3.0 or if you install ZDS-II at any location other than the default location, you will have to modify three files: (1) arch/arm/z80/src/ez80/Kconfig, (2) configs/makerlisp/scripts/Make.defs and, perhaps, (3) arch/z80/src/ez80/Toolchain.defs. Serial Console ============== There are two options for a serial console: (1) A UART connected to a terminal program or (2) the MakerLisp Serial Keyboard and VGA display. UARTs ----- The eZ80 has two UART peripherals: UART 0: All of Port D pins can support UART0 functions when configured for the alternate function 7. For typical configurations only RXD and TXD need be configured. eZ80 PIN BOARD SIGNAL CN1 ACCESS ======================================= PD0/TXD0/IR_IXD CN1_TX0 Pin 61 PD1/RXD0/IR_RXD CN1_RX0 Pin 59 PD2/RTS0 CN1_RTS0 Pin 63 PD3/CTS0 CN1_CTS0 Pin 65 PD4/DTR0 CN1_DTR0 Pin 67 PD5/DSR0 CN1_DSR0 Pin 69 PD6/DCD0 CN1_DCD0 Pin 71 PD7/RIO0 CN1_RI0 Pin 73 UART0 (as well as I2C) is also available via a USB using the on-board MCP2221A USB adapter. CN1_USBUART_TX_EN and CN1_USBUART_RX_EN are pulled low poll on the CPU board in order to connect CN1_RX0 and CN1_TX0 to MCP_RX and MCP_TX. When the I/O expander board is connected, jumpers J1 and J2 control this functionality. These can pull the CN1_USBUART_TX_EN and CN1_USBUART_RX_EN pins high and so that UART0 can be used for other purposes. UART 1: All of Port C pins can support UART1 functions when configured for the alternate function 7. For typical configurations only RXD and TXD need be configured. eZ80 PIN BOARD SIGNAL CN1 ACCESS ======================================= PC0/TXD1 CN1_TX1 Pin 62 PC1/RXD1 CN1_RX1 Pin 60 PC2/RTS1 CN1_RTS1 Pin 64 PC3/CTS1 CN1_CTS1 Pin 66 PC4/DTR1 CN1_DTR1 Pin 68 PC5/DSR1 CN1_DSR1 Pin 70 PC6/DCD1 CN1_DCD1 Pin 72 PC7/RIO1 CN1_RI1 Pin 74 With the I/O exanpander board (and J1 and J2 open), these UARTs can be used with a host terminal emulation, by connecting either a TTL-to-RS232 or a TTL-to-USB Serial adapter to CN1 pins 59 and 61, and 60 and 62, depending on the selected UART. Serial Keyboard and VGA Display ------------------------------- The serial console can also be implemented using the MakerLisp USB Keyboard Controller Board and VGA Display Controller. These are accessed via the one UART port, UART0. In the default MakerLisp configuration. These boards are connected as follows: 1. VGA display controller connections (UART0 TX) Board interface header 5 – 5V regulated power input RX – VGA Display Controller serial input C – VGA Display Controller ready output TX – VGA Display Controller serial output G – GND Connections: a. 5V '5' pin on VGA board to expansion board power distribution 5V. b. Ground 'G' pin on VGA board to expansion board power distribution ground. c. Receive 'RX' pin on VGA board to expansion board GPIO PD0 (TXD0). d. Communication, terminal ready indicator 'C' pin on VGA board to expansion board GPIO PB1. e. Transmit 'TX' pin on VGA board to USB keyboard controller 'R' To use the VGA display controller with stdout and stderr, you also need to selection CONFIG_MAKERLISP_VGA=y in your configuration. This enables a required VGA initialization sequence. 2. USB keyboard controller (UART0 RX) Board interface header 5 – 5V regulated power input R – USB Keyboard Controller serial input T – USB Keyboard Controller serial output G – GND Connections: a. 5V '5' pin on USB board to (other) expansion board power distribution 5V. b. Ground 'G' pin on USB board to (other) expansion board power distribution ground. c. Receive 'R' pin on USB board to VGA board 'TX' (see above). d. Transmit 'T' pin on USB board to expansion board GPIO PD1 (RXD0). If your keyboard does not seem to be doing anything, check the 'RX' jumper on the expansion board. For input from a USB keyboard, and NOT the USB/UART connection, you want this jumper REMOVED, not bridging the two header pins front to back. The PC terminal software should be configured as described in the MakerLisp Putty HOWTO document: 115200N1 BAUD. Default Serial Console ---------------------- UART0 is the default serial console in all configurations unless otherwise noted in the description of the configuration. LEDs and Buttons ================ LEDs ---- Three LEDs are available on the CPU Card, but none are available for general use by applications: D2 RED: CPU Card power. Not under eZ80 control D3 GREEN: Driven by CPU GPI/O pin. However, it has some additional properties: 1. On input, it will be '1' if the I/O expansion board is present. 2. Setting it to an output of '0' will generate a system reset. 3. Setting it to an output of '1' will not only illuminate the LED take the card out of reset and enable power to the SD card slot. As a consequence, the GREEN LED will not be illuminated if SD card support or SPI is disabled. The only effect of CONFIG_ARCH_LEDS is that the GREEN LED will turned off in the event of a crash. D1 AMBER: Controlled by the on-board MCP2221A USB bridge and provides USB enumeration status. Not under eZ80 control. Buttons ------- The MakerLisp CPU board has no on-board buttons that can be sensed by the eZ80. Configurations ============== Common Configuration Notes -------------------------- 1. src/ and include/ These directories contain common logic for all MakerLisp configurations. 2. Variations on the basic MakerLisp configuration are maintained in subdirectories. To configure any specific configuration, do the following steps: tools/configure.sh [OPTIONS] makerlisp/ make Where is the specific board configuration that you wish to build. Use 'tools/configure.sh -h' to see the possible options. Typical options are: -l Configure for a Linux host -c Configure for a Windows Cygwin host -g Configure for a Windows MYS2 host Use configure.bat instead of configure.sh if you are building in a native Windows environment. The available board-specific configurations are summarized in the following paragraphs. When the build completes successfully, you will find this files in the top level nuttx directory: a. nuttx.hex - A loadable file in Intel HEX format b. nuttx.lod - A loadable file in ZDS-II binary format c. nuttx.map - A linker map file 3. ZDS-II make be used to write the nuttx.lod file to FLASH. General instructions: a. Start ZDS-II b. Open the project, for example, nsh/nsh.zdsproj c. Select Debug->Connect To Target d. Select Debug->Download code There are projects for the ZiLOG Smart Flash Programmer as well but these are not functional as of this writing. 4. This configuration uses the mconf-based configuration tool. To change this configurations using that tool, you should: a. Build and install the kconfig-mconf tool. See nuttx/README.txt see additional README.txt files in the NuttX tools repository. b. Execute 'make menuconfig' in nuttx/ in order to start the reconfiguration process. Configuration Subdirectories ---------------------------- nsh: This configuration builds the NuttShell (NSH). That code can be found in examples/nsh. For more information see: examples/nsh/README.txt and Documentation/NuttShell.html. NOTES: 1. A serial console is provided on UART0. This configuration should work with or without the the VGA and Keyboard adapter boards. Normal connectivity is via host serical console connected through the USB serial console. Withe the I/O expansion board, the serial console can also be sued with either a TTL-to-RS232 or a TTL-to-USB Serial adapter connected by CN1 pins 59 and 61. The default baud setting is 115200N1. To use the VGA display controller with stdout and stderr, you also need to selection CONFIG_MAKERLISP_VGA=y in your configuration. This enables a required VGA initialization sequence. The PC terminal software should be configured as described in the MakerLisp Putty HOWTO document: 115200N1 BAUD.